在形态动态铜协调复合体中快速电子转移自我交换
Paul J Griffin1, Lisa Olshansky1
1Department of Chemistry, Center for Biophysics and Quantitative Biology, and Materials Research Laboratory, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States.
Journal of the American Chemical Society
|September 8, 2023
概括
我们发现具有dpa连接体的动态铜复合体表现出极快的电子转移率. 这种形状的灵活性与蓝铜蛋白的刚性不同,是有效的电子转移的关键.
科学领域:
- 无机化学
- 生物有机化学
- 物理化学
背景情况:
- 在生物和化学系统中,电子转移 (ET) 是基本的.
- 铜复合物是重要的催化剂和电子转移媒介.
- 了解影响ET速率的因素对于设计高效的分子系统至关重要.
研究的目的:
- 为了研究 CuII/I 复合物与 dpaR 配体的电子转移自交速常数 (k11).
- 将铜复合物的结构动态与其ET效率相关联.
- 将这些复合物的ET特性与蓝铜蛋白质进行比较.
主要方法:
- 使用核磁共振 (NMR) 线路扩展实验来确定速率常数.
- 合成和表征铜复合物与二聚聚氨 (dpa) 配体,特别是dpaOMe和dpaSMe.
- 在不同氧化状态下分析铜复合物的结构动力学.
主要成果:
- 报告的 [CuCl (dpaOMe) ]+/0 (2.48 × 10^5 M^-1 s^-1) 和 [CuCl (dpaSMe) ]+/0 (2.21 × 10^6 M^-1 s^-1) 的大k11值.
- [CuCl ((dpaSMe) ]+/0复合体表现出分子铜复合体中最快的ET速率之一,与蓝铜蛋白相美.
- 在CuI (dpaOMe) 或CuII (dpaSMe) 复合体中的 conformational 动力学导致最小化的内部球体重组能量 (分别为0.71和0.62 eV).
结论:
- 在铜复合体中,dpaR配体促进的 conformational 动态性显著提高了电子转移速率.
- 这一发现与对蓝色铜蛋白的化状态模型的强调形成鲜明对比.
- 这项研究强调了动态形态平衡在分子系统中调解快速电子转移的重要性.
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