大豆种子贮藏蛋白11S与7S组份的研究

大豆种子球蛋白组份的组成与蛋白品质密切相关。本实验利用SDS—PAGE梯度电泳分离11S球蛋白和7S伴球蛋白各亚基，通过软件Gel—pro analysis3．0计算了1757份大豆种质中11S和7S的相对含量(以蛋白亚基吸光值计算)以及11S／7S比值，结果表明，1757份大豆种子球蛋白11S／7S比值的变异幅度在0．72～2．99内，平均值为1．885；不同品种间亚基组份存在亚基含量和亚基缺失的变异，揭示了我国大豆遗传资源的多样性。大豆品种11S／7S比值在不同大豆生态区存在显著性差异，说明大豆11S／7S比值的高低具有一定的生态适应性；地方品种与育成品种的比较表明，同一生态区或同一省份地方品种11S／7S平均值显著高于育成品种：大豆种子粗蛋白含量的高低和11S／7S比值相关性不大，但是以大豆种子粗蛋白含量在40％～49％范围内．11S／7S比值在不同生态区之间的变异最为显著。

The Analysis of 11S/7S in Soybean Storage Protein

The quality of soybean protein is greatly correlative to the value of 11S/7S in soybean seeds. In this study, the subunits of 11S globulin and 7S glycoglobulin were isolated with SDS-PAGE gradient electrophoresis. The contents of 11S and 7S were figured out according to their optical density(OD value ) and the 11S/7S ratios were also calculated. The values of 11S/7S in 1757 soybean accessions showed that 11S/7S in soybean seeds varied from 0.7-2.99, averaged 1.885. The change of the subunit content and the absence of different subunit in soybean seeds indicated the abundant genetic diversity in Chinese soybean. Among several eco-regions, the mean values of 11S/7S showed significant difference, which suggests that the 11S/7S value in soybean seeds depends on the environment in a great degree. We still found that in a same eco-region, the average value of 11S/7S for developed varieties were much higher than that for local varieties. Although the correlation between 11S/7S and protein content in soybean seeds was not obvious, for the soybean seeds with protein content within the range of 40%-49%, the average 11S/7S ratio showed significant change in different eco-regions.