不同环境下沙冬青属植物的蛋白质氨基酸变化

Change of the Protein Amino Acid Content in Ammopiptanthus Cheng f. under the Different Habitats

对 2种沙冬青叶和种子中蛋白质结合氨基酸及种子游离氨基酸的组成成分进行测定 ,其结果显示 :9种主要结合氨基酸含量之和占总氨基酸含量的 73.71%～ 76 .0 7% ,反映了属内种遗传的一致性。不同器官中的氨基酸组成含量不同 ,并随生存环境的改变而发生变化。总的趋势是 ,栽培条件下总结合氨基酸及大部分结合氨基酸含量高于野生状态 ;蒙古沙冬青(Ammopiptanthusmongolicus) 总结合氨基酸及大部分结合氨基酸含量稍高于新疆沙冬青 (A .nanus)。在吐鲁番沙漠植物园栽培条件下 ,沙冬青种子中结合氨基酸的含量大于叶中的含量 ;两种沙冬青叶中含有一定量的Cys(半胱氨酸 ) ,而种子中几乎不含Cys。总游离氨基酸的绝对含量范围在 2 .10～ 12 .5 1mg/g·dr.wt;均含有较高的Asp(天门冬氨酸 )、Glu(谷氨酸 )、Ser(丝氨酸 )和Arg(精氨酸 ) ,Met(蛋氨酸 )、Ile (异亮氨酸 )、Leu(亮氨酸 )和Gly(甘氨酸 )含量普遍较低。种间种子游离氨基酸组分含量差异明显 ,栽培条件下种子中主要的游离氨基酸含量有明显提高 ,其中Pro(脯氨酸 )和Asp含量分别是野生状态下的 2 .4和 4 .1倍。结合引种栽培区的气候环境因子分析 ,这些游离氨基酸含量的变化与植物受到一定程度的干旱胁迫有关联。

In this paper, the content and composition of amino acid in leaves and seeds of 2 species of Ammopiptanthus Cheng f. are measured and researched. The results show that the percentage of the total content of 9 combinative amino acids in the total amino acid varies in a range of 73.71%～76.07%, which reveal the genetic consistency of the different species. The compositive contents of amino acid are different from the different parts of plants, and vary with the change of habitats. Generally, the contents of total combinative amino acid and most of the combinative amino acids under cultivation are higher than that under the natural conditions. The contents of total combinative amino acid and most of the combinative amino acids of Ammopiptanthus mongolicus are slightly higher than that of A. nanus. Under cultivation in Turpan Desert Botanic Garden, the content of combinative amino acid in seeds is higher than that in leaves of Ammopiptanthus Cheng f. Some Cys is contained in leaves but not in seeds. The absolute content of total free amino acid varies in a range of 2.10 mg/g·dr·wt～12.51 mg/g·dr·wt with high contents of Glu, Asp, Arg and Ser but low content of Met, Ile, Leu and Gly. The difference of content and composition of free amino acid in seeds between the different species of Ammopiptanthus Cheng f. is obvious. The contents of Pro and Asp under cultivation are 2.4 and 4.1 times higher respectively than that under the natural conditions. By considering the climatic and environmental factors in the cultivation area, the analysis reveals that the change of the contents of these free amino acids is related to the drought stress to a certain extent.