Dipartimento di Chimica G. Ciamician, Università di Bologna, V. F. Selmi 2, 40126, Bologna, Italy.
J Phys Chem B. 2010 Mar 25;114(11):4101-6. doi: 10.1021/jp101093z.
The short answer to the title question is that it acts as an electrostatic bouncer that shoves the charge flow from flavin toward the DNA lesion that photolyase repairs. This explanation is provided by an explicit time-dependent quantum mechanical approach, which is used to investigate the electron transfer process that triggers the repair mechanism. The transfer occurs from the flavin photolyase cofactor to the cyclobutane ring of DNA, previously formed by light-induced cycloaddition of adjacent pyrimidine bases. The electron wave function dynamics accurately accounts for the previously proposed mechanism of transfer via the terminal methyl group of the flavin moiety present in the catalytic electron-donor cofactor, FADH(-), which also contains adenine. This latter moiety, which has often been assumed to be present mainly for structural reasons, instantaneously modifies the interaction between acceptor and donor by a variation of the electrostatic interactions so that the presence of its local atomic charges is necessary to trigger the transfer. In principle, knowledge of the details of the electron transfer dynamics and of the important role of polarization effects can be exploited to improve the efficiency of the repair mechanism in artificial systems.
标题问题的简短答案是，它充当静电弹弓，将电荷流从黄素推向光解酶修复的 DNA 损伤。这个解释是通过一个明确的含时量子力学方法提供的，该方法用于研究触发修复机制的电子转移过程。转移发生在黄素光解酶辅因子和先前由相邻嘧啶碱基光诱导环加成形成的 DNA 环丁烷环之间。电子波函数动力学准确地说明了通过存在于催化电子供体辅因子 FADH(-)中的黄素部分的末端甲基基团进行转移的先前提出的机制，该辅因子还包含腺嘌呤。这个后者部分通常被认为主要是由于结构原因而存在，通过改变静电相互作用瞬时修改了受体和供体之间的相互作用，使得其局部原子电荷的存在对于触发转移是必要的。原则上，可以利用电子转移动力学的细节以及极化效应的重要作用的知识来提高人工系统中修复机制的效率。
