检查Pseudomonas aeruginosa azurin中的光诱导能量转移
Peter H Tobin1, Corey J Wilson
1Department of Chemical and Environmental Engineering, ‡Department of Biomedical Engineering, and §Department of Molecular Biophysics and Biochemistry, Yale University , New Haven, Connecticut 06520-8286, United States.
Journal of the American Chemical Society
|January 29, 2014
概括
在Pseudomonas aeruginosa azurin中,电子转移 (EleT) 速率可能被错误地归因于能量转移 (EngT). 青中的污染可以模仿EleT,而EngT在光敏剂和铜部位之间观察到.
科学领域:
- 生物物理化学 生物物理化学
- 蛋白质的电子转移是蛋白质的电子转移
- 频谱学是一种光谱学.
背景情况:
- 伪菌 (Pseudomonas aeruginosa azurin) 是一个用于研究电子转移 (EleT) 的模型蛋白.
- 之前的研究使用了光敏感剂来研究EleT,数据为理论模型提供了信息.
- 已使用光诱导方法来测量青中的EleT率.
研究的目的:
- 调查替代机制,特别是能量转移 (EngT),这可能解释观察到的光诱导动力学在青.
- 解决污染和兴奋状态排放等可能导致动力数据误解的混因素.
- 使用不同的光敏感剂系统,在青系统中区分光诱导的EngT和EleT.
主要方法:
- 使用了两种以为基础的光敏化系统:Ru(bpy) 2 ((imidazole) 和Ru(bpy) 2 ((phen-IA).
- 采用广泛的金属分析来检测和量化潜在的污染物.
- 进行电化学和光化学 (光诱导转移) 测量以分析反应动力学.
- 研究了污染和兴奋状态排放在观察到的动力特征中的作用.
主要成果:
- 鉴定出青中污染是 biexponential反应动力学的来源,经常被误认为是EleT.
- 证明了对比反应的缓慢阶段归因于Zn-金属化青,而不是EleT.
- 表明光敏剂和铜位点之间的EngT导致了快速相衰变,而不是简单的兴奋状态衰变.
结论:
- 在Pseudomonas aeruginosa azurin模型系统中的光诱导运动速率可以通过EngT解释,而不仅仅是EleT.
- 污染是一个关键的混因素,可能导致错误的EleT.分配.
- 区分EngT和EleT需要仔细分离实验变量和先进的分析技术.
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