Abstract：
Edible plant seeds provide a relatively inexpensive source of protein and make up a large part of nutrients for humans. Plant seeds accumulate storage proteins during seed development. Seed storage proteins act as a reserve of nutrition for seed germination and seedling growth. However, seed storage proteins may be allergenic, and the prevalence of food allergy has increased rapidly in recent years. The 11S globulins account for a significant number of known major food allergens. They are of interest to the public and the agricultural industry because of food safety concerns and the need for crop enhancement. We sought to determine the crystal structure of Cor a 9, the 11 S storage protein of hazelnut and a food allergen. The structure was refined to 1.92 Å, and the R and Rfree for the refined structure are 17.6% and 22.5%, respectively. The structure of Cor a 9 showed a hetero hexamer of an 11S seed storage protein for the first time. The hexamer was two trimers associated back-to-back. Two long alpha helixes at the C-terminal end of the acidic domain of one of the Cor a 9 isoforms lay at the trimer-trimer interface\'s groove. These data provided much-needed information about the allergenicity of the 11S seed proteins. The information may also facilitate a better understanding of the folding and transportation of 11S seed storage proteins.
摘要：
可食用植物种子提供了相对便宜的蛋白质来源，并构成了人类的大部分营养素。植物种子在种子发育过程中积累贮藏蛋白。种子贮藏蛋白作为种子萌发和幼苗生长的营养储备。然而,种子储存蛋白可能是过敏原，近年来，食物过敏的患病率迅速增加。11S球蛋白占大量已知的主要食物过敏原。由于食品安全问题和作物改良的需要，它们引起了公众和农业的兴趣。我们试图确定Cora9，榛子的11S储存蛋白和食物过敏原的晶体结构。结构被精炼到1.92贝达，精化结构的R和Rfree分别为17.6%和22.5%，分别。Cor一9的结构首次显示11S种子贮藏蛋白的异型六聚体。六聚体是背靠背相关的两个三聚体。Cor9同种型之一的酸性结构域的C末端有两个长α螺旋位于三聚体-三聚体界面的凹槽处。这些数据提供了有关11S种子蛋白变应原性的急需信息。这些信息还可能有助于更好地理解11S种子储存蛋白的折叠和运输。
