PROTEIN DYNAMIC EFFECTS ON BIOLOGICAL ELECTRON TRANSFER

描述 隧道效应是一种量子力学效应。这只对小公司很重要 质子和电子等粒子。标准过渡态理论 可以成功地应用于大多数反应，但以下反应除外 转移小粒子(质子或电子)。在转移的反应中 质子或电子隧穿可以使反应速度看起来比 从标准的过渡态理论中可以预料到。这是因为 质子或电子可以避免越过标准过渡态。 障碍物，可以从它下面直接出现在另一边 障碍的边缘。这是可能的，因为小粒子强烈地 受测不准原理的影响，存在一个非零概率 粒子可以在一个位置找到，它的势能 超过粒子的总能量。对于电子转移反应， 描述电子的位置和能量的波函数可以达到 超过(或低于)较高的电子转移能垒。那里 是电子出现在地球另一侧的有限概率。 障碍物，从来没有越过障碍物，因为它的波函数 决定了它存在的可能性是有限的。 非弹性隧穿，这个FIRCA拟议研究的主要主题， 包括矩阵的运动(它不做康登假设)。 对于非弹性隧穿来说，核运动有可能是 再加上电子转移过程，以促进电子 转移这给电子额外的能量，通过 电子-声子耦合，以帮助它完成转移。第页的图2 提案的21部分说明了非弹性隧道模型(包括 原子核运动的影响)优于弹性隧穿模型(不 包括原子核运动的影响)来描述远程率 Ru修饰细胞色素中的电子转移。 总而言之，看来非弹性隧道效应(包括 核运动)对于远距离生物电子转移是重要的 如光合作用中THOS和氧化过程中的电子传递 新陈代谢。

DESCRIPTION Tunneling is a quantum mechanical effect. It is only important for small particles such as protons and electrons. Standard transition state theory can be successfully applied to most reactions, except for those which transfer small particles (protons or electrons). In reactions that transfer protons or electrons tunneling can make reaction rates appear faster than would be expected from standard transition state theory. This is because the proton or electron can avoid going over the standard transition state barrier and can instead go beneath it to directly appear on the other side of the barrier. Thi is possible because small particles are strongly affected by the uncertainty principle and there is a nonzero probability that the particle can be found at a position where the potential energy exceeds the particle's total energy. For an electron transfer reaction the wave function describing the position and energy of the electron can reach beyond (or beneath) the higher energy barrier for electron transfer. There is a finite probability that the electron will appear on the other side of the barrier, without ever going over the barrier, because its wave function dictates that there is a finite probability that it can be there. Inelastic tunneling, the main topic of the proposed research for this FIRCA, includes the motion of the matrix (it doesn't make the Condon assumption). For inelastic tunneling there is the possibility that nuclear motions can be coupled with the electron transfer process to facilitate the electron transfer This gives additional energy to the electron, through electron-phonon coupling to help it complete the transfer. Figure 2 on page 21 of the proposal illustrates how the inelastic tunneling model (including effects of nuclear motion) is superior to elastic tunneling model (not including effects of nuclear motion) in describing the rate of long-range electron transfers in Ru-modified cytochromes. In summary, it appears that inelastic tunneling (including effects of nuclear motion) is important for long-range biological electron transfers such as thos in photosynthesis and electron transport in oxidative metabolism.