Characterization of Low Molecular Weight Allergens from English Walnut (Juglans regia)
Characterization of Low Molecular Weight Allergens from English Walnut (Juglans regia)
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DOI：
10.1021/jf504672m
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发表时间：
2014-12-03
影响因子：
6.1
通讯作者：
Mills, E. N. Clare
中科院分区：
文献类型：
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作者：
Downs, Melanie L.;Semic-Jusufagic, Aida;Mills, E. N. Clare
尽管英国核桃是一种常见的致敏坚果，但迄今为止，核桃过敏原的特征还很不清楚。这项工作的目的是表征核桃中天然的低分子量 (LMW) 过敏原。开发了一种从英国核桃中纯化 LMW 过敏原（特别是 2S 白蛋白）的方案。除了 2S 白蛋白之外，还鉴定并表征了来自 7S 种子储存球蛋白原蛋白 N 末端区域的一系列肽。这些肽包含在 7S N 末端区域重复的四个半胱氨酸基序 (C-X-X-X-C-X10-12-C-X-X-X-C)。 IgE 免疫印迹显示，来自核桃过敏受试者的 3/11 和 5/11 血清分别显示出对 7S N 末端片段和 2S 白蛋白的 IgE 反应性。成熟的 7S 蛋白和新描述的 7S N 端肽代表两种不同类型的过敏原。由于许多食用植物物种中 7S 球蛋白的蛋白水解过程尚未阐明，因此类似的蛋白质片段可能存在于其他坚果和种子中。
Although English walnut is a commonly allergenic tree nut, walnut allergens have been poorly characterized to date. The objective of this work was to characterize the natural, low molecular weight (LMW) allergens from walnut. A protocol was developed to purify LMW allergens (specifically 2S albumins) from English walnuts. In addition to 2S albumins, a series of peptides from the N-terminal region of the 7S seed storage globulin proprotein were also identified and characterized. These peptides comprised a four-cysteine motif (C-X-X-X-C-X10-12-C-X-X-X-C) repeated throughout the 7S N-terminal region. Upon IgE immunoblotting, 3/11 and 5/11 sera from walnut-allergic subjects showed IgE reactivity to the 7S N-terminal fragments and 2S albumin, respectively. The mature 7S protein and the newly described 7S N-terminal peptides represent two distinct types of allergens. Because the proteolytic processing of 7S globulins has not been elucidated in many edible plant species, similar protein fragments may be present in other nuts and seeds.