Simulation of the electron transfer between the tetraheme subunit and the special pair of the photosynthetic reaction center using a microstate description.
Simulation of the electron transfer between the tetraheme subunit and the special pair of the photosynthetic reaction center using a microstate description.
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使用微观状态描述模拟四血红素亚基和光合反应中心的特殊对之间的电子转移。
DOI：
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发表时间：
2007
影响因子：
3.3
通讯作者：
G. Ullmann
中科院分区：
文献类型：
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作者：
T. Becker;R. Ullmann;G. Ullmann
通过生物大分子的电荷转移对于许多生物过程是必不可少的，例如光合作用和呼吸作用。质子或电子分别在可滴定残基或氧化还原活性辅因子之间转移。这些位点之间的转移速率取决于邻近位点的当前电荷配置。在这里，我们以微观状态的形式描述了电荷传递系统的动力学。一个独特的传递速率常数可以分配给微观状态的相互转换。参与转移反应的位点之间的相互作用自然被考虑在内。将此公式应用于绿芽草藻四血红素亚基和反应中心特殊对的电子转移动力学。结果表明，连续统静电计算可以与已有的经验速率定律相结合，得到电子传递速率常数。在微观状态下模拟的光氧化特殊对的再还原动力学与实验数据吻合较好。通量分析用于跟踪各个电子转移步骤。
Charge transfer through biological macromolecules is essential for many biological processes such as, for instance, photosynthesis and respiration. Protons or electrons are transferred between titratable residues or redox-active cofactors, respectively. Transfer rates between these sites depend on the current charge configuration of neighboring sites. Here, we formulate the kinetics of charge-transfer systems in a microstate formalism. A unique transfer rate constant can be assigned to the interconversion of microstates. Mutual interactions between sites participating in the transfer reactions are naturally taken into account. The formalism is applied to the kinetics of electron transfer in the tetraheme subunit and the special pair of the reaction center of Blastochloris viridis. It is shown that continuum electrostatic calculations can be used in combination with an existing empirical rate law to obtain electron-transfer rate constants. The re-reduction kinetics of the photo-oxidized special pair simulated in a microstate formalism is shown to be in good agreement with experimental data. A flux analysis is used to follow the individual electron-transfer steps.