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谷氨酰胺合成酶是植物氮代谢途径中的关键酶,分为胞液型(GS1)和质体型(GS2)两种。本文首次从苎麻中克隆了一个胞液型谷氨酰胺合成酶基因BnGS1-1,并利用生物信息学对其序列和结构特征进行了分析。该基因序列全长1205 bp,含有一个1071 bp的ORF区,编码356个氨基酸残基的多肽,pI和Mw分别为5.64和39.19 KDa,具有beta-Grasp和catalytic两个保守功能域;蛋白序列在56、92、249和297位点分别为Asp、Cys、His和Glu。系统进化分析表明BnGS1-1与大豆(Glycine max)、四季豆(Phaseolus vulgaris)、苜蓿(Medicago sativa)、棉花(Gossypium raimondii)在同一个分支上。同时,将BnGS1-1与pBI121载体利用同源重组技术,成功构建了植物超量表达载体。因此,本研究为了解和改善苎麻饲用特性提供了物质和理论基础。
Glutamine synthetase is a key enzyme in plant nitrogen metabolism, which is divided into cytosolic (GS1) and plastid (GS2). In this paper, a cytosolic glutamine synthetase gene BnGS1-1 was cloned from ramie for the first time, and its sequence and structural characteristics were analyzed by bioinformatics. The full length of this gene was 1205 bp and contained a 1071 bp ORF region encoding a polypeptide of 356 amino acid residues with pI and Mw of 5.64 and 39.19 KDa, respectively. The sequence contained two conserved domains, beta-Grasp and catalytic. The 56, 92, 249 and 297 sites were Asp, Cys, His and Glu, respectively. Phylogenetic analysis showed that BnGS1-1 was on the same branch as Glycine max, Phaseolus vulgaris, Medicago sativa and Gossypium raimondii. Meanwhile, BnGS1-1 and pBI121 vectors were successfully constructed by using homologous recombination technology. Therefore, this study provided the material and theoretical basis for understanding and improving the feeding characteristics of ramie.