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光系统II的键网络中的 conformational 变化稳定了进化氧的复合体

Brandon P Russell¹, David J Vinyard¹

¹Department of Biological Sciences, Louisiana State University, 202 Life Sciences Building, Baton Rouge, LA 70803, United States of America.

Biochimica et biophysica acta. Bioenergetics

|November 13, 2023

概括

光系统II (PSII) 中的D1-R334G突变影响了氧进化复合体 (OEC) 的稳定性和PsbO结合. 这表明D1-R334键网络在PsbO相互作用之前在OEC组装过程中具有明显的形状.

科学领域:

光合作用研究研究光合作用.
植物生物化学植物生物化学
分子生物学分子生物学

背景情况:

光系II (PSII) 中的Mn4CaO5氧化复合体 (OEC) 对于水的氧化至关重要.
该PsbO子单元稳定了OEC,并帮助OEC组装后的质子转移.
D1残留物R334参与质子释放,并与PsbO相互作用,显示结构变化.

研究的目的:

研究PSII和OEC组件中的D1残留R334的功能.
了解D1-R334键网络在OEC稳定性和PsbO相互作用中的作用.

主要方法:

在Synechocystis sp.中产生了一个D1-R334G点突变. 这是PCC 6803.
在不同的光照条件下评估PSII活动和OEC稳定性.
对PsbO结合和含量的孤立核心复合物进行分析.
研究了突变体中S2中间体的稳定.

主要成果:

D1-R334G PSII在连续光线下是活跃的,但在黑暗中显示OEC不稳定性.
与野生类型相比,孤立的D1-R334G核心复合体表现出较低的PsbO结合和较低的含量.
在D1-R334G突变体中,S2中间体稳定,表明OEC环境发生了变化.
这些发现表明,在PsbO对接之前的OEC生物发生过程中,D1-R334网络的功能构造不同.

结论:

D1-R334残留物及其相关的键网络在OEC稳定性和正确的PsbO相互作用中发挥着关键作用.
在PsbO结合之前的OEC组装过程中,D1-R334网络的形状不同,影响的纳入和稳定性.

关键词:

联网是联网的组成部分.进化氧的复合体是如何演变的摄影系统II 摄影系统II 质子运输是一种质子运输.水的氧化方式.

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