Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan 030006, PR China.
Food Chem Toxicol. 2012 Aug;50(8):2675-80. doi: 10.1016/j.fct.2012.03.039. Epub 2012 Mar 17.
Fag t 1, a legumin-type protein, is the major allergen in tartary buckwheat. In the current study, three recombinant derivatives of Fag t 1, designated as Fag t 1-rs1, Fag t 1-rs2, and Fag t 1-rs3, were constructed via rational design and genetic engineering. However, because of the loss of their native-like folds, the Fag t 1 derivatives failed to bind IgE, and their allergenic activities were reduced. The recombinant hypoallergenic variants are promising vaccine candidates for specific immunotherapy of buckwheat allergy. The unfolding of the Fag t 1 structure reduced its high resistance to gastrointestinal proteolysis and strongly reduced its IgE reactivity. The derivatives showed a more than 90% reduction in allergenic activity compared with rFag t 1. These results suggest that the structure-dependent stability of 11S seed storage proteins is directly related to digestive stability and allergenic potential. Therefore, the destruction of the native conformation is the appropriate strategy to reduce the allergenicity of the cupin family food allergens.
Fag t 1 是一种豆科蛋白，是苦荞中的主要过敏原。在本研究中，通过合理设计和基因工程构建了三种重组 Fag t 1 衍生物，分别命名为 Fag t 1-rs1、Fag t 1-rs2 和 Fag t 1-rs3。然而，由于它们失去了天然折叠，Fag t 1 衍生物无法与 IgE 结合，其变应原活性降低。这些重组低变应原变体是荞麦过敏特异性免疫治疗的有前途的疫苗候选物。Fag t 1 结构的展开降低了其对胃肠道蛋白水解的高抗性，并强烈降低了其 IgE 反应性。与 rFag t 1 相比，衍生物的变应原活性降低了 90%以上。这些结果表明 11S 种子贮藏蛋白的结构依赖性稳定性与消化稳定性和变应原潜力直接相关。因此，破坏天然构象是降低 cupin 家族食物过敏原变应原性的合适策略。
