As fish is one source of the ‘big eight’ food allergens,the prevalence of fish allergy has increased over the past few years.In order to better understand fish allergy,it is necessary to identify fish allergens.Based on the sera from fish-allergenic patients,a 28 kDa protein from local mackerel (Scomber japonicus),which has not been reported as a fish allergen,was found to be reactive with most of the patients’ sera.The 28 kDa protein was analyzed by MALDI-TOF-MS (Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry).Mascot search in NCBI database (Date: 08/07/2010) showed that the top protein matched,i.e.triosephosphate isomerase (TPI) from Xiphophorus maculatus and Poecilia reticulata,had a mowse (molecular weight search) score of 98.In addition,TPI from Epinephelus coioides also matched this mackerel protein with a mowse score of 96.Because TPI is con-sidered as an allergen in other non-fish organisms,such as lychee,wheat,latex,archaeopotamobius (Archaeopotamobius sibiriensis) and crangon (Crangon crangon),we consider that it may also be an allergen in mackerel.
WANG Bangping LI Zhenxing ZHENG Lina LIU Yixuan LIN Hong
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。
