为了进一步认识褐虾中的一种过敏原——磷酸丙糖异构酶过敏原(Cra c 8)的结构与功能关系,理解食物过敏原之间产生交叉反应的分子基础,采用生物信息学方法分析Cra c 8蛋白的理化性质和各级结构,探讨其与食物中该蛋白质在分子水平上的异同。结果表明:褐虾Cra c 8蛋白是由249个氨基酸组成的酸性蛋白质,与螯虾、对虾、三文鱼、小麦、蟑螂中的磷酸丙糖异构酶蛋白具有较高的同源性,亲疏水性区域相似;二级结构预测结果显示其以α-螺旋和不规则折叠为主,均没有β-折叠及β-转角区域;利用同源建模的方式成功的构建褐虾Cra c 8蛋白的空间结构。
To further understand the structure-function relationship of the allergen Cra c 8 of triosephosphate isomerase (TPI) from brown shrimps (Crangon crangon) and the molecular basis of cross reaction among food allergens, physical and chemical properties as well as the difference and similarity between Cra c 8 and other triosephosphate isomerases at molecular level were analyzed by a series of bioinformatics softwares. The results showed that Cra c 8 protein was an acidic protein composed of 249 amino acids. The homology of similar proteins was relatively high and hydrophobic and hydrophilic areas had great similarity in Archaeopotamobius sibiriensis, Fenneropenaeus chinensis, Salmo salar, Triticum aestivum and Blattella germanica. The prediction results of secondary structure showed that α -helix and irregular folds were the major structures of Cra c 8 protein, while β -sheet and β-comer regions were absent. The spatial structure of Cra c 8 protein was successfully built by homology modeling. This study will provide a theoretical reference for exploring the activity and cross-reactivity properties of brown shrimp Cra c 8 protein.