Essen L O, Klar T
Department of Chemistry, Philipps University, Hans-Meerwein-Strasse, 35032 Marburg, Germany.
Cell Mol Life Sci. 2006 Jun;63(11):1266-77. doi: 10.1007/s00018-005-5447-y.
DNA photolyases are highly efficient light-driven DNA repair enzymes which revert the genome-damaging effects caused by ultraviolet (UV) radiation. These enzymes occur in almost all living organisms exposed to sunlight, the only exception being placental mammals like humans and mice. Their catalytic mechanism employs the light-driven injection of an electron onto the DNA lesion to trigger the cleavage of cyclobutane- pyrimidine dimers or 6-4 photoproducts inside duplex DNA. Spectroscopic and structural analysis has recently yielded a concise view of how photolyases recognize these DNA lesions involving two neighboring bases, catalyze the repair reaction within a nanosecond and still achieve quantum efficiencies of close to one. Apart from these mechanistic aspects, the potential of DNA photolyases for the generation of highly UV-resistant organisms, or for skin cancer prevention by ectopical application is increasingly recognized.
DNA光解酶是高效的光驱动DNA修复酶，可逆转紫外线（UV）辐射对基因组造成的损伤。这些酶几乎存在于所有暴露于阳光的生物体中，唯一的例外是像人类和小鼠这样的胎盘哺乳动物。它们的催化机制是利用光驱动将一个电子注入到DNA损伤部位，从而引发双链DNA中环丁烷嘧啶二聚体或6-4光产物的裂解。光谱学和结构分析最近对光解酶如何识别涉及两个相邻碱基的这些DNA损伤、在纳秒内催化修复反应并仍能实现接近1的量子效率给出了一个简明的观点。除了这些机制方面，DNA光解酶在培育高度抗紫外线生物或通过局部应用预防皮肤癌方面的潜力也越来越受到认可。
