【作者】 胡伟； 王呈坤； 梁晶丹； 张天龙； 胡中培； 王志军； 蓝文贤； 李芳； 吴厚铭； 丁建平； 吴更； 邓子新； 曹春阳；

【Author】 Wei Hu1§,Chengkun Wang1§,Jindan Liang2,Tianlong Zhang3,Zhongpei Hu1,4,Zhijun Wang2,Wenxian Lan1,Fang Li4,Houming Wu1,Jianping Ding3,Geng Wu2,Zixin Deng2,Chunyang Cao1(1.State Key Laboratory of Bio-organic and Natural Product Chemistry,Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,345 Lingling Road,Shanghai 200032,China;2.Laboratory of Microbial Metabolism,and School of Life Sciences and Biotechnology,Shanghai Jiao Tong University,Shanghai 200030,China;3.Institute of Biochemistry and Cell Biology,Shanghai Institutes for Biological Sciences,Shanghai 200031,China;4.Central China Normal University,Wuhan 430079,China)

【机构】 中国科学院上海有机化学研究所生命有机化学国家重点实验室； 上海交通大学微生物代谢国家重点实验室； 中国科学院上海生命科学研究院生物化学与细胞生物学研究所； 华中师范大学；

【摘要】 <正>DNA磷硫修饰是人类发现的第一种生理性的DNA骨架修饰,这种修饰具有序列专一性,立体选择性,分布广泛性。研究表明,DndE蛋白是控制生理体内DNA磷硫酰化修饰的五个基因编码的蛋白之一,但是其如何发挥功能还有待进一步研究。借助NMR技术,我们发现DndE蛋白在Trish缓冲体系中构象均一。在此基础上,我们解析了来自大肠杆菌B7a中的DndE蛋白的晶体结构,表明DndE蛋白是一种带缺口dsDNA结合蛋白,而不是基于更多还原

【Abstract】 DNA Phosphorothioation(PT) modification with sulfur replacing a nonbridging phosphate oxygen was recently discovered as a product of five dnd genes found in bacteria and archaea.However,the understanding on its biological functions is extremely limited.The studies on the proteins involved in PT modification are mostly performed based on bioinformatical analysis,especially,the functional prediction on how DndE acts remains unclear.Here we report the crystal structure of DndE from Escherichia coli B7A,indicating that it works as neither a sulfotransferase nor a NCAIR synthase analogue.Our fluorescence polarization binding assay and site-directed mutation studies suggest that DndE might be a nicked double stranded DNA binding protein and plays a role in recognizing a nick in PT modification sequence during biochemical pathway of DNA PT modification.更多还原