荧光蛋白生色团成熟机理的理论研究

项目名称： 荧光蛋白生色团成熟机理的理论研究

项目编号： No.21303009

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 马莹莹

作者单位： 内蒙古工业大学

项目金额： 25万元

中文摘要： 绿色荧光蛋白不仅能够发出稳定的荧光，而且其生色团的成熟是一个自催化的过程，不需要任何的辅因子。因此，绿色荧光蛋白生色团的成熟机理不仅是一个重要而有趣的理论问题，还可以帮助人们合成出成熟速率更快、荧光更稳定、颜色更亮的荧光蛋白变体，具有广泛的应用价值。本研究主要包括三个方面：1）探索出野生型绿色荧光蛋白生色团成熟机理完整的图像。成熟机理主要包括三个步骤，环化-氧化-脱水，本研究将对这三个步骤的具体机理给出清晰的图像。2）之前的研究表明有些变体能够加快绿色荧光蛋白生色团的成熟速率，本研究将对绿色荧光蛋白生色团成熟机理中的构效关系做进一步研究。3)指明红色荧光蛋白DsRed生色团的成熟机理。本研究主要利用分子动力学（MD）、密度泛函理论（DFT）和量子力学/分子力学（QM/MM）相结合的方法,来解决上述问题。

中文关键词： 荧光蛋白；生色团成熟机理；QM/MM方法；密度泛函理论；

英文摘要： Green fluorescent proteins (GFPs) are particularly useful not only due to the fluorescence they can display, but also to their stabilities and the fact that the chromophores are formed in an autocatalytic cyclization of a peptide from their own backbone structure that does not require a cofactor. Understanding of the mechanism of the autocatalytic post-translation reaction of GFP will be beneficial in designing brighter and faster mutants, thereby increasing their utility in biotechnology and cell biology. Our studies involves three aspects: First, investigating the mechanism of chromophore maturation in GFP. The chromophore maturation process in GFP comprises three steps, which is cyclization, oxidation and dehydration. The mechanism of these three stpes will be explored. Second, mature GFP is most efficiently formed at temperatures well below 37 ℃. This has limited the uses of GFP, especially in mammalian cells, and leading to search for GFP mutants that mature more efficiently at higher temperatures. Some mutants can improve chromophore maturation efficiency, these structure-activity relationship will be studied. Third, the red-emitting FPs (RFPs) are of particular importance as suitable marker for mammalian deep tissue imaging. Most of the RFPs share a DeRed-like chromophore, and the mechanism of DsRed -lik

英文关键词： fluorescent protein；mechanism of chromophore maturation；QM/MM；DFT；