Identification of sesame seed allergens by 2-dimensional proteomics and Edman sequencing: Seed storage proteins as common food allergens
Identification of sesame seed allergens by 2-dimensional proteomics and Edman sequencing: Seed storage proteins as common food allergens
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DOI：
10.1067/mai.2002.125487
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发表时间：
2002-07-01
影响因子：
14.2
通讯作者：
Sampson, HA
中科院分区：
文献类型：
--
作者：
Beyer, K;Bardina, L;Sampson, HA
背景：芝麻过敏正变得越来越普遍，可能是因为它在国际快餐和烘焙产品中的使用。目的：研究芝麻种子中的致敏蛋白，为芝麻种子过敏性蛋白的鉴定提供理论依据。用来自20名芝麻过敏患者的个体患者血清进行免疫标记。结果：在78、52、45、34、32、29、25、20、9和7kd处鉴定出了特异性IgE结合蛋白。分析内部序列，发现被75%的患者识别的45kd的蛋白质是7S豌豆球蛋白型球蛋白，芝麻的种子储存蛋白，并命名为Ses i 3。7kd处的蛋白质被发现是2S白蛋白，其是芝麻的另一种种子贮藏蛋白，并被命名为Ses i 2。种子贮藏蛋白是花生、核桃、巴西坚果和大豆中已知的食物过敏原。有趣的是，花生过敏原Ara h 1的一个已知IgE结合表位与Ses i 3的相应区域具有80%的同源性。不同的氨基酸先前被证明是不关键的IgE结合在Ara h 1。另外，在78和34 kd处的蛋白质分别与大豆的胚胎丰富蛋白和种子成熟蛋白同源。结论：4种芝麻过敏原的鉴定是构建重组过敏原用于未来免疫学方法的第一步。此外，在常见的食物过敏原的保守IgE结合表位的检测可能是一个有用的工具，用于预测交叉反应，某些食物。
Background: Sesame seed allergy is becoming increasingly prevalent, probably because of its use in international fast-food and bakery products. Despite this fact, few studies have focused on the identification of its major allergenic proteins.Objective: The aim of this study was to identify allergenic proteins of sesame seeds (Sesamum indicum).Methods: Extracted sesame seed proteins were separated by means of SDS-PAGE and 2-dimensional (2-D) PAGE. Immunolabeling was performed with individual patient sera from 20 patients with sesame seed allergy. Selected proteins were further analyzed by, means of Edman sequencing.Results: IgE-binding proteins were identified at 78, 52, 45, 34,32, 29, 25, 20, 9, and 7 kd. Analyzing internal sequences, the protein at 45 kd, which was recognized by 75% of the patients, was found to be a 7S vicilin-type globulin, a seed storage protein of sesame and named Ses i 3. The protein at 7 kd was found to be a 2S albumin, another seed storage protein of sesame and named Ses i 2. Seed storage proteins are known food allergens in peanut, walnut, Brazil nut, and soybean. Interestingly, one known IgE-binding epitope of the peanut allergen Ara h 1 has 80% homology with the corresponding area of Ses i 3. The different amino acids were previously shown not to be critical for IgE binding in Ara h 1. In addition, the proteins at 78 and 34 kd were found to be homologous to the embryonic abundant protein nd the seed maturation protein of soybeans, respectively.Conclusion: The identification of 4 sesame seed allergens is the first step toward generating recombinant allergens for use in future immunotherapeutic approaches. In addition, the detection of conserved IgE binding epitopes in common food allergens might be a useful tool for predicting cross-reactivity to certain foods.