在光合作用反应中心,脂质与胡卜素结合部位的结合
Sasmit S Deshmukh1, Kai Tang, László Kálmán
1Department of Physics, Concordia University, Montreal, Quebec H4B 1R6, Canada.
Journal of the American Chemical Society
|September 8, 2011
概括
脂质与光合作用反应中心的结合显著延长了电荷分离状态的寿命. 这一发现为使用生物电容器的光驱储能应用开辟了新的途径.
科学领域:
- 生物化学 生物化学
- 光合作用 光合作用
- 结构生物学 结构生物学
背景情况:
- 在Rhodobacter sphaeroides的反应中心中,不活跃的细菌单体离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子离子.
- 野生型反应中心的光诱导结构变化改变了局部介电常数,增加了电荷分离状态的寿命.
- 没有胡卜素的突变R-26缺乏胡卜素,允许对脂质相互作用进行特定的探测.
研究的目的:
- 为了研究R-26突变反应中心的胡卜素结合部位的脂质结合.
- 为了确定脂质结合和光引起的结构变化对电荷分离状态寿命的影响.
- 确定储能领域的潜在应用.
主要方法:
- 使用了来自Rhodobacter sphaeroides的没有胡卜素的突变R-26.
- 嵌入反应中心到蛋白质体中.
- 使用生物物理技术探测了脂质结合和光诱导的结构变化.
- 在不同条件下研究的电荷分离状态寿命.
主要成果:
- 脂质结合与光诱导的结构变化相结合,R-26反应中心的电荷分离状态寿命增加了五个数量级.
- 在特定的冷却条件下,和脂与C12和C14脂肪酸链成功结合.
- 在光合作用反应中心内确定了一个新的脂质结合部位.
结论:
- 脂质相互作用在稳定光合作用反应中心的电荷分离中起着至关重要的作用.
- 这些发现表明,光合作用反应中心的潜在应用是作为光驱动的生物电容器来储存能量.
- 在生理温度下延长的电荷分离状态寿命证明了这种方法的可行性.
相关概念视频
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The pigment molecules are arranged across two photosystem domains — the antenna complex and the reaction center. The main aim of the pigment molecules...
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01:15The Antenna Complex
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01:32Photosystems
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