花生种子贮藏蛋白的热稳定性与氨基酸组成的关系  

Relation of Heat Stability of Storage Proteins and Amino Acid Composition in Peanut Seeds

作　　者：芦春斌[1] 黄上志[2] 傅家瑞[2] 

机构地区：[1]暨南大学生殖免疫中心,广州510632 [2]中山大学生命科学学院,广州510275

出　　处：《种子》2001年第3期3-5,20,共4页Seed

基　　金：广东省自然科学基金! (950 0 90 )资助课题

摘　　要：分析两种不同蛋白类型的花生种子贮藏蛋白热稳定性 ,表明各品种类型花生种子贮藏蛋白的 3种主要组分的的热稳定性存在显著的差异 ,即伴花生球蛋白 热稳定性最高 ,伴花生球蛋白 次之 ,花生球蛋白最低。高甲硫氨酸品种类型 (汕油 5 2 3)的贮藏蛋白中无论花生球蛋白还是伴花生球蛋白 的热稳定性都高于低甲硫氨酸品种类型 (海花 1号 )相应组分的热稳定性。氨基酸分析表明 ,各品种 3种组分中 17种氨基酸中的大多数氨基酸含量无显著变化 ,并且天冬氨酸 ,谷氨酸和精氨酸的含量最高 ,三者之和可达总量的 45 %以上 :3种组分中 ,伴花生球蛋白 除了谷氨酸和精氨酸含量显著高于花生球蛋白 ,伴花生球蛋白 外 ,含硫氨基酸 (甲硫氨酸和半胱氨酸 )也明显高于后两者。 3个组分中含硫氨基酸水平与热稳定性正相关 ,即含硫氨基酸水平越高 ,其热稳定性越高。冷藏过程中含硫氨基酸高的伴花生球蛋白 不易降解、保持高热稳定性水平。Heat stability of storage proteins in methionine rich peanut (Cultivar Shanyou 523)and methionine poor peanut (Cultivar Haihua 1) were studied. Results showed that heat stability of arachin and conarachin Ⅱ in Shanyou 523 was much higher than those in Haihua 1.Heat stability of conarachin Ⅱ was the highest in both cultivars. Heat stability of conarachin Ⅰwas middle, but that of arachin was the lowest. Amino acid compositions of their 3 major components showed that. Asparatic acid, Glutamic acid and Arginine were highest level, totally about 45%.2 sulfur containing amino acids(Met, Cys) were extremely low level. The sulfurcontaining amino acids level of Conarachin Ⅱ in 3 major components was the highest in both cultivars. The levels of 2 sulfur containing amino acids (Met, Cys), Arg and Glu of Conarachin Ⅱ were much higher than those of arachin and conarachin Ⅰ in both cultivars. Based on this result, it was concluded that the highest levels of Met and Cys in 3 components were related to high heat stability. Changes of free amino acids and heat stability between arachin and conarachin Ⅱ showed that methionine richest conarachin Ⅱ was kept heat stability due to not to be degraded during cold storge.

关 键 词：花生种子 贮藏蛋白 氨基酸组成 热稳定性 

分 类 号：S565.2[农业科学—作物学]