对AbrB C端结构域的置换分析揭示了其在DNA结合活性中的重要作用。

Neubauer Svetlana, Dolgova Olga, Präg Gregory, Borriss Rainer, Makarewicz Oliwia

Institute of Biology, Humboldt University of Berlin, Berlin, Germany.

Institute of Biology, Humboldt University of Berlin, Berlin, Germany; Center for Infectious Diseases and Infection Control, Jena University Hospital, Jena, Germany.

PLoS One. 2014 May 15;9(5):e97254. doi: 10.1371/journal.pone.0097254. eCollection 2014.

The global transition state regulator AbrB controls more than 100 genes of the Bacillus relatives and is known to interact with varying DNA-sequences. The DNA-binding domain of the AbrB-like proteins was proposed to be located exclusively within the amino-terminal ends. However, the recognition of DNA, and specificity of the binding mechanism, remains elusive still in view of highly differing recognition sites. Here we present a substitutional analysis to examine the role of the carboxy-terminal domain of AbrB from Bacillus subtilis and Bacillus amyloliquefaciens. Our results demonstrate that the carboxy-terminal domains of AbrB affect the DNA-binding properties of the tetrameric AbrB. Most likely, the C-termini are responsible for the cooperative character observed for AbrB interaction with some DNA targets like tycA and phyC.

全局过渡态调节因子AbrB控制芽孢杆菌属相关菌的100多个基因，并且已知其与不同的DNA序列相互作用。有人提出，类AbrB蛋白的DNA结合结构域仅位于氨基末端。然而，鉴于识别位点差异很大，DNA的识别以及结合机制的特异性仍然难以捉摸。在此，我们进行了一项替换分析，以研究枯草芽孢杆菌和解淀粉芽孢杆菌中AbrB的羧基末端结构域的作用。我们的结果表明，AbrB的羧基末端结构域影响四聚体AbrB的DNA结合特性。最有可能的是，C末端负责观察到的AbrB与某些DNA靶标（如tycA和phyC）相互作用的协同特性。