A structural sketch of RcdA, a transcription factor controlling the master regulator of biofilm formation
A structural sketch of RcdA, a transcription factor controlling the master regulator of biofilm formation
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RcdA 的结构示意图，一种控制生物膜形成主调节因子的转录因子
DOI：
10.1002/1873-3468.12713
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Hirata Akira
中科院分区：
文献类型：
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作者：
Sugino Hirotaka;Usui Takanori;Shimada Tomohiro;Nakano Masahiro;Ogasawara Hiroshi;Ishihama Akira;Hirata Akira
RcdA是curlin亚基基因D的调控因子，而curlin亚基基因D是大肠杆菌生物膜形成的主要调控因子。在这里，我们以2.55 Å分辨率确定了RcdA的X射线结构。RcdA由一个N端DNA结合域（DBD）和一个C端二聚化域组成，并在晶体中形成同二聚体。RcdA - DNA复合物的计算对接模型允许预测负责DNA结合的候选残基。我们的结构导向诱变，结合凝胶位移实验、原子力显微镜观察和报告基因实验，表明HTH基序α2中的R32在靶DNA的识别和结合中起重要作用，而α3中的T46影响寡聚化模式。这些结果为RcdA的DNA结合模式提供了新的见解。
RcdA is a regulator of curlin subunit gene D, the master regulator of biofilm formation inEscherichia coli. Here, we determined the X‐ray structure of RcdA at 2.55 Å resolution. RcdA consists of an N‐terminal DNA‐binding domain (DBD) containing a helix‐turn‐helix (HTH) motif and a C‐terminal dimerization domain, and forms a homodimer in crystals. A computational docking model of the RcdA‐DNA complex allowed prediction of the candidate residues responsible for DNA binding. Our structure‐guided mutagenesis, in combination with gel shift assay, atomic force microscopic observation, and reporter assay, indicate that R32 in α2 of the HTH motif plays an essential role in the recognition and binding of target DNA while T46 in α3 influences the mode of oligomerization. These results provide insights into the DNA‐binding mode of RcdA.