Cu^(2+)对苦荞过敏蛋白TBt的结构和IgG结合能力的影响  

Effects of Cu^(2+) on Molecular Structure and IgG Binding Capacity of the Tartary Buckwheat Allergic Protein TBt

作　　者：杨欢[1] 崔晓东[1] 李玉英[1] 王转花[1] 

机构地区：[1]山西大学生物技术研究所,化学生物学与分子工程教育部重点实验室,山西太原030006

出　　处：《食品科学》2014年第5期28-32,共5页Food Science

基　　金：国家自然科学基金面上项目(31171659);太原市科技攻关项目(100622)

摘　　要：TBt是苦荞中的主要过敏蛋白,为了研究Cu2+对其结构及致敏性的影响,本实验采用荧光光谱法探讨Cu2+与TBt的相互作用;圆二色光谱及非变性聚丙烯酰胺凝胶电泳测定其结构变化;间接性酶联免疫和抑制性酶联免疫法鉴定C u2+对TBt的IgG结合能力的影响。结果表明:Cu2+和TBt之间存在相互作用,二者以浓度比1∶1形成稳定的复合物;圆二色光谱分析表明,TBt的二级结构并未发生明显的改变;但非变性聚丙烯酰胺凝胶电泳分析显示,Cu2+与TBt作用后,可促使TBt由三聚体进一步聚合形成六聚体。同时抑制性酶联免疫和间接性酶联免疫也表明,Cu2+与TBt作用形成六聚体后,由于抗原决定簇被部分遮挡,与IgG抗体结合能力降低。This study aimed to examined the effect of Cu2＋ on the structure and allergenicity of TBt, a major allergen in tartary buckwheat. Experiments were carried out to explore the interaction between TBt and Cu2＋ by fluorescence spectroscopy, analyze the structural change of TBt by circular dichroism （CD） spectroscopy and native polyacrylamide gel electrophoresis （PAGE）, and identify the effect of Cu2＋ on its IgG binding capacity by indirect ELISA and inhibitory ELISA. The results of the fluorescence spectroscopic analysis indicated that Cu2＋ could be bound to TBt at a molar ratio of 1：1. CD analysis showed the secondary structure of TBt did not change, but the spatial structure of TBt was changed in native PAGE. Briefly, the spatial structures of TBt changed into hexamers after interaction with Cu2＋. Inhibitory ELISA and indirect ELISA showed that TBt became a hexamer, and a part of epitopes were covered and the IgG binding capacity was decreased.

关 键 词：苦荞麦 过敏蛋白 金属离子 致敏性 

分 类 号：Q516[生物学—生物化学] R392[医药卫生—免疫学]