苯丙氨酸生物合成关键酶基因pheA与aroF协同表达  

Coordinated expression of two key enzyme genes pheA and aroF in phenylalanine biosynthesis pathway

作　　者：芦佳[1] 黄坤央[2] 赵越[1] 徐琪寿[3] 郭军[1] 黄英武[4] 

机构地区：[1]内蒙古农业大学食品科学与工程学院,内蒙古呼和浩特010018 [2]郑州大学药学院,河南郑州450001 [3]军事医学科学院放射与辐射医学研究所,北京100850 [4]中国人民解放军306医院中心实验室,北京100101

出　　处：《食品工业科技》2012年第2期210-213,共4页Science and Technology of Food Industry

摘　　要：目的:优化L-苯丙氨酸生物合成通路上的关键酶基因pheA、aroF的蛋白表达,构建高产L-苯丙氨酸的工程菌株。方法:通过设计酶基因的间隔调控序列,分别构建重组质粒pZE12-RBS-AF和pZE12-AF,SDS-PAGE观察蛋白表达量,转入营养缺陷菌MGΔ中构建工程菌,并发酵培养。结果:工程菌MGΔpZE12-AF苯丙氨酸的产量比工程菌MGΔpZE12-RBS-AF高1倍,实现了L-苯丙氨酸生物合成关键酶基因pheA和aroF协同,匹配表达。结论:调整串联酶基因之间的间隔调控序列可实现苯丙氨酸合成酶基因的协同表达,提供了一种新的提高苯丙氨酸工程菌产量的方法。Objective：To develop a metabolically engineered E..coli strain for the overproduction of L-phenylalanine through optimization of protein expressions of two key genes pheA and aroF involved in L-phenylalanine biosynthesis pathway.Methods：We constructed two recombinant plasmids pZEI2-RBS-AF and pZE12-AF based on designing the DNA sequences of intergenic regulatory region between pheA and aroF.PheA and aroF protein expressions were observed by SDS-PAGE.Engineered E.coli strains were obtained by transforming the above two plasmids into an auxotrophic strain MGA and fermented for L- phenylalanine production.ResuLts： L- phenylalanine yield of the engineered strain MG△pZE12-AF was almost twice as high as that of the engineered strain MG△pZE12 -RBS-AR It was achieved by coordinated tandem expression of pheA and aroR Conclusion： Coordinated expression of L- phenylalanine biosynthesis enzymes can be obtained by adjusting intergenic regulatory sequences between tandem enzyme genes. It provides a new approach to improve the yield of engineered L-phenylalanine producing strain.

关 键 词：L-苯丙氨酸 间隔调控序列 协同表达 

分 类 号：Q786[生物学—分子生物学]