大肠杆菌天冬氨酸激酶lysC基因的克隆及定点突变  

Cloning and Site-Directed Mutagenesis of lysC Gene Encoding Aspartokinase of Escherichia coli K12

作　　者：赵倩[1] 刘俊起 敖光明[1] 

机构地区：[1]中国农业大学农业生物技术国家重点实验室,北京100094

出　　处：《农业生物技术学报》1999年第4期348-352,共5页Journal of Agricultural Biotechnology

基　　金："863"项目;国家自然科学基金

摘　　要：以大肠杆菌K12菌株，总DNA为模板，利用PCR技术扩增了编码天冬氨酸激酶的lysC基因。序列分析结果表明，目的基因含有1350个核苷酸（包括起始密码和终止密码），与文献报道相比，核苷酸序列同源率为99．6％，推测的氨基酸序列与报道的相比，同源率为99．3％利用定点突变方法，将核苷酸序列的第1055位的C变成T，从而引起第352位的苏氨酸变为异亮氨酸，以改变天冬氨酸激酶对赖氨酸反馈抑制的敏感性。The lysC gene encoding the lysine-sensitive aspartokinase of Escherhoia coli K12 was amplified by PCR using total DNA as templatc. Sequence analysis indicated the isolated fragment was composed of 1 35O bp. It has 99.6 % homology to the sequence reported by Cassan et al. The deduced arnino acid sequence shares 99.3 % identity with the reported gene. A nucleic acid mutation was induced at 1 055 site, which resulted in an isoleucine for threonine substitution at amino acid 352.

关 键 词：天冬氨酸激酶 基因 序列 定点突变 大肠杆菌 

分 类 号：S432.42[农业科学—植物病理学]