植物Kunitz蛋白酶抑制剂的生物信息学分析

Bioinformatics Analysis of Kunitz Protease Inhibitors in Plants

运用生物信息学的方法,对已在GenBank数据库中注册的大豆、海红豆、凤凰木、象耳豆及洋紫荆等植物Kunitz蛋白酶抑制剂的氨基酸序列进行分析。结果显示,这些植物的Kunitz蛋白酶抑制剂中甘氨酸、谷氨酸、亮氨酸、丝氨酸、天冬氨酸及缬氨酸含量较丰富;不同植物Kunitz蛋白酶抑制剂的氨基酸序列具有较高的同源性,其中P1位点的氨基酸残基序度保守;分子进化研究表明Kunitz蛋白酶抑制剂可作为植物遗传分化和分子进化研究的重要依据;部分序列中存在信号肽;分子中不存在跨膜结构域,可能受蛋白激酶C的磷酸化;无规卷曲是多肽链中的主要结构元件;分子中包含典型的STI功能结构域。

Bioinformatic methods were employed to analyze the amino acid sequences of Kunitz protease inhibitors from Genbank database,such as Glycine max,Adenanthera pavonina,Delonix regia,Enterolobium contortisiliquum,Bauhinia variegata.The results were as bellow,Leu,Gly,Glu,Val,Ser and Asp were abundant in those Kunitz protease inhibitors.Sequence alignment revealed that Kunitz protease inhibitors were highly homologous in plants.The P1 site residue was highly conservative.Kunitz protease inhibitors could be used as genetic differentiation and an important basis for the study of molecular evolution.There was a conserved signal peptide in segmental plants.Kunitz protease inhibitor had no transmembrane structure and could be phosphorylated by protein kinase C,with the potential phosphorylated site Ser148.Random coils were the major structural element of polypeptide chain.Meanwhile,Kunitz protease inhibitors contained typical function domains of STI.