大肠杆菌O157:H7紧密黏附素空间结构建模研究

3D-structure modeling of Enterohemorrhagic Escherichia coli O157:H7 intimin

肠出血性大肠杆菌O157:H7紧密黏附素是一种致病性相关的跨膜蛋白,C端区域具有免疫原性。本研究以肠致病性大肠杆菌的紧密黏附素C端空间结构为模板,利用Build Homology Models同源建模构建目标序列——肠出血性大肠杆菌O157:H7紧密黏附素,C端区域的部分空间结构模型。对模型空间结构的合理性通过Verify-3D程序进行评估,Ramachandram图谱和残基相容性评分结果显示,构建出的模型结构合理,各氨基残基的空间排布整体相容性较高.模型多为β型结构,非球状,本研究可为进一步通过空间结构模型进行特异性抗体、适体的设计以及筛选提供理论基础。

Enterohemorrhagic Escherichia coli O157：H7 （EHEC） intimin was a protein which gives expression to closen relationship between bacteria and virulence. BLAST had been used to search for the similar sequences and structures to C- terminal region of intimin. After multiple sequences alignment, the known 3D structure of chosen similar sequence （Enteropathogenic Escherichia coli infimin） severed as the template for EHEC intimin 3D structure modeling, And the model configurations were refined and analyzed by bioinformatics sotiwares. The diagram of Ramachandram and Verify-3D showed that the model accord with the stereochemistry and the overall compatibility of this model was credible. Intimin 3D structure mainly included β-sheets and β-turn, and holded a non-spherical shape. The research provided a basis for the further antibody and aptamer design.