Investigating the interactions between DNA and DndE during DNA phosphorothioation
Investigating the interactions between DNA and DndE during DNA phosphorothioation
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研究 DNA 硫代磷酸化过程中 DNA 和 DndE 之间的相互作用
DOI：
10.1002/1873-3468.13529
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发表时间：
2019
期刊：
影响因子：
3.5
通讯作者：
Cao Chunyang
中科院分区：
文献类型：
--
作者：
Yao Penfei;Liu Yaping;Wang Chengkun;Lan Wenxian;Wang Chunxi;Cao Chunyang
DNA硫代磷酸酯修饰是细菌中一种新的生理变异。DndE通过与dsDNA结合来控制这种修饰，其机制尚不清楚。野生型DndE四聚体的结构分析表明，其中心带正电荷的区域对DNA结合很重要。在本研究中，我们用赖氨酸取代了该区域中的残基G21和G24，这增加了DNA结合亲和力，但不影响DNA降解表型。突变体的结构分析表明，它形成了一个新的四聚体构象，DndE与DNA相互作用作为一个单体，而不是作为一个四聚体。DndE-DNA复合物的结构模型，基于其结构同源物P22 Arc阻遏物，表明DndE中的两个柔性环是DNA结合的决定因素
The DNA phosphorothioate modification is a novel physiological variation in bacteria. DndE controls this modification by binding to dsDNA via a mechanism that remains unclear. Structural analysis of the wild‐type DndE tetramer suggests that a positively charged region in its center is important for DNA binding. In the present study, we replaced residues G21 and G24 in this region with lysines, which increases the DNA binding affinity but does not affect the DNA degradation phenotype. Structural analysis of the mutant indicates that it forms a new tetrameric conformation and that DndE interacts with DNA as a monomer rather than as a tetramer. A structural model of the DndE–DNA complex, based on its structural homolog P22 Arc repressor, indicates that two flexible loops in DndE are determinants of DNA binding