Conformational changes in cytochrome c and cytochrome oxidase upon complex formation: a resonance Raman study.
Conformational changes in cytochrome c and cytochrome oxidase upon complex formation: a resonance Raman study.
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复合物形成时细胞色素 c 和细胞色素氧化酶的构象变化：共振拉曼研究。
DOI：
10.1021/bi00458a044
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发表时间：
1990
期刊：
影响因子：
2.9
通讯作者：
Powell,GL
中科院分区：
文献类型：
--
作者：
Hildebrandt,P;Heimburg,T;Marsh,D;Powell,GL
彼得·希尔德布兰特，*，t，§Thomas Heimburg，1，11 Derek Marsh，1和Gary L.Powell1 Max-Planck-Institifür biPhysisikalische Chemie，Abteilung Spektroskopie，D-3400 Gottingen，FRG，以及南卡罗来纳州克莱姆森大学生物科学系29634-1903年8月23日收到；修改稿收到10月16日，摘要：用共振拉曼光谱研究了在低离子强度下形成的细胞色素c和细胞色素氧化酶的完全氧化的络合物。使用Soret带激发在较宽的频率范围内比较了络合物和单个组分的光谱。在复合体的两个配对中，血红素基团和它们直接的蛋白质环境都发生了结构变化。该复合体在16 0 0-17 0 0 cm-1频率范围内的谱带以细胞色素氧化酶组分为主，而在30 0-5 0 0 cm™1范围内的谱带以细胞色素c组分为主，从而允许将贡献从两个单独的物种中分离出来。对于细胞色素c，观察到了光谱变化，这对应于诱导构象I和状态II的六配位低自旋构型与细胞色素氧化酶结合。虽然状态I的细胞色素c的结构与溶液中的结构基本相同，但状态II的特点是血红素口袋的结构重排，导致轴向铁-蛋氨酸键的减弱和位于细胞色素氧化酶结合区域中心的血红素缝隙的开口。两种细胞色素c状态在络合物中的相对贡献率约为1：1。认为细胞色素c向细胞色素氧化酶的电子转移是由呈现不同氧化还原电势的态I和态II之间的构象平衡控制的。可归因于血红素a的光谱变化是通过细胞色素氧化酶蛋白基质与血红素基团的外围取代基相互作用结合细胞色素c的变化来解释的。特别是甲酰基的迁移率降低。这些结构变化可能反映了血红素正确排列的建立，这是一个电子转移的基团。对血红素A3共振拉曼光谱的细微影响归因于卟啉的电子系统与相邻氨基酸侧链的相互作用的改变，表明细胞色素c结合部位与血红素A3口袋之间存在结构联系。还原的细胞色素c与部分氧化的氰化物连接的细胞色素氧化酶之间的络合物的光谱也表明，这些氧化还原伙伴发生了构象变化。E细胞色素c(Cyt C)1到细胞色素氧化酶(Cyt ox；EC 1.9)的电子转移反应。3.1)构成了需氧生物呼吸链的末端(Dickerson&Timkovich，1975；Pettigrew&Moore，1987)。细胞色素c的假体基团是血红素c，它提供将分子氧还原为水所需的电子。这个过程与三磷酸腺苷的合成有关，三磷酸腺苷是代谢过程的最终化学能量来源。Cyt ox含有四个可还原位点，两个血红素(a，A3)和两个铜中心(Cua，Cub)(Wikstróm等人，1981)。在氧化还原过程的第一步，铁细胞色素c与跨越膜的细胞色素氧化酶的胞液面紧密结合。这种复合体通过…周围带正电的富含赖氨酸的结构域之间的强烈静电相互作用而结合在一起
Peter Hildebrandt,*, t, § Thomas Heimburg, 1, 11 Derek Marsh, 1 and Gary L. Powell1 Max-Planck-Instituí für biophysikalische Chemie, Abteilung Spektroskopie, D-3400 Gottingen, FRG, and Department of Biological Sciences, ClemsonUniversity, Clemson, South Carolina 29634-1903 Received August 23, 1989; Revised Manuscript Received October 16, 1989 abstract: The fully oxidized complex of cytochrome c and cytochrome oxidase formed at low ionic strength was studied by resonance Raman spectroscopy. The spectra of the complex and of the individual components were compared over a wide frequency range using Soret band excitation. In both partners of the complex, structural changes occur in theheme groups and in their immediate protein environment. Thespectra of the complex in the 1600-1700 cm-1 frequency range were dominated by bands from the cytochrome oxidase component, whereas those in the 300-500 cm™ 1 range were dominated by bands from the cytochrome c component, hence allowing separation of the contributionsfrom thetwo individual species. For cytochrome c, spectral changes were observed which correspondto the induction of the conformational state I and the six-coordinated low-spin configuration of state II on binding to cytochrome oxidase. While instate I the structure of cytochrome c is essentially the same as in solution, state II is characterized by a structural rearrangement of the heme pocket, leading to a weakening of the axial iron-methionine bond and an opening of the heme crevice which is situated in the center of the binding domain for cytochrome oxidase. The relative contributions of the two cytochrome c states were estimated to be approximately in the ratio 1: 1 in the complex. It is proposed that the electron transferfrom cytochrome c to cytochrome oxidase is controlled by the conformational equilibrium between the states I and II which exhibit different redox potentials. The spectral changes assignable to heme a are interpreted in terms of alterations in the interaction of the cytochrome oxidase protein matrix with the peripheral substituents of the heme group, on binding cytochrome c. It is suggested that, in particular, the mobility of the formyl group is reduced. These structural changes may reflect the establishment of the proper alignment of the heme a group for the electron transfer. Subtle effects on the resonance Raman bands of heme a3 are attributed to modified interactions of the-electron systems of the porphyrin with adjacent amino acid side chains, suggesting that there is a structural communication between the cytochrome c binding site and the heme a3 pocket. Spectra of the complex between the reduced cytochrome c and the partially oxidized cyanide-ligated cytochrome oxidasealso indicated that conformational changes take place in these redoxpartners. e electron-transfer reaction from cytochrome c (cyt c) 1 to cytochrome oxidase (cyt ox; EC 1.9. 3.1) constitutes the terminal step of the respiratory chain of aerobic organisms (Dickerson & Timkovich, 1975; Pettigrew & Moore, 1987). Cyt c, whose prostheticgroup is a heme c, delivers the electrons required for the reduction of molecular oxygen to water. This process is coupled tothe synthesis of ATP, the ultimate source of chemical energy for metabolic processes. Cyt ox contains four reducible sites, two hemes (a, a3) and two copper centers (Cua, Cub)(Wikstróm et al., 1981). In the first step of the redox process, ferrocytochrome c binds tightly to the cytosolic face of the membrane-spanning cytochrome oxidase enzyme. This complex is held together via strong electrostatic interactions between the positively charged lysine-rich domain around the …
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自旋标记心磷脂与二肉豆蔻酰磷脂酰胆碱取代的牛心细胞色素 c 氧化酶的关联。
DOI：
10.1016/0005-2736(85)90409-2
发表时间：
1985
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
G. Powell;P. Knowles;D. Marsh
通讯作者：
D. Marsh
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
马细胞色素 C 和酵母细胞色素 C 过氧化物酶非共价复合物的质子 NMR 研究及其与其他相互作用蛋白复合物的比较。
DOI：
10.1016/0167-4838(87)90251-2
发表时间：
1987
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
Satterlee,JD;Moench,SJ;Erman,JE
通讯作者：
Erman,JE
细胞色素 c 氧化酶作为电子传输驱动的质子泵：周转期间氧化还原中心还原水平的 pH 依赖性。
影响因子：
2.9
作者：
Per;P. Brzezinski;Fredriksson Po;B. Malmström
通讯作者：
B. Malmström
细胞色素 c 氧化酶-细胞色素 c 复合物的光谱分析：圆二色性和磁性圆二色性测量揭示了复合物形成引起的细胞色素 c 血红素几何形状的变化。
DOI：
10.1073/pnas.84.19.6687
发表时间：
1987
影响因子：
11.1
作者：
Christoph Weber;Bruno Michel;H. Bosshard
通讯作者：
H. Bosshard