Bagchi Angshuman
Department of Biochemistry and Biophysics, University of Kalyani, Kalyani, Nadia, India.
Gene. 2015 Jan 10;554(2):249-53. doi: 10.1016/j.gene.2014.10.044. Epub 2014 Oct 30.
Pasteurella multocida is responsible behind a variety of diseases in animals. The disease causing substance of this bacterium is a capsular polysaccharide. The expression of the gene that codes for the bacterial capsule is regulated by the protein Fis. Fis also regulates the expression of various different genes in P. multocida. So far there have been no previous reports that depict the characterization of Fis from P. multocida from a structural point of view. In the present work, an attempt has been made to characterize Fis by in silico methods. The structure of Fis was built by comparative modeling technique. The model of Fis was then docked onto the corresponding promoter regions of the gene encoding the capsular polysaccharide. The docked complexes of promoter DNA with Fis protein were subjected to molecular dynamics simulations to identify the mode of DNA-protein interactions. The DNA binding amino acid residues from the Fis protein were identified. And a mechanistic detail of the DNA binding interactions was predicted. So far, this is the first report that depicts the mechanistic details of Fis-DNA interactions involved in the regulation of gene expression by Fis protein. This work may therefore be useful to illuminate the still obscure molecular mechanism behind the disease propagation by P. multocida.
多杀性巴氏杆菌是多种动物疾病的病因。这种细菌的致病物质是一种荚膜多糖。编码细菌荚膜的基因的表达受蛋白质Fis调控。Fis还调控多杀性巴氏杆菌中各种不同基因的表达。到目前为止，尚无从结构角度描述多杀性巴氏杆菌Fis特征的先前报道。在本研究中，尝试通过计算机模拟方法对Fis进行特征描述。通过比较建模技术构建了Fis的结构。然后将Fis模型对接至编码荚膜多糖的基因的相应启动子区域。对启动子DNA与Fis蛋白的对接复合物进行分子动力学模拟，以确定DNA-蛋白质相互作用的模式。鉴定了Fis蛋白中与DNA结合的氨基酸残基。并预测了DNA结合相互作用的机制细节。到目前为止，这是第一份描述Fis蛋白调控基因表达过程中Fis-DNA相互作用机制细节的报告。因此，这项工作可能有助于阐明多杀性巴氏杆菌疾病传播背后仍不清楚的分子机制。
