多基因在大肠杆菌中的共表达策略

多基因共表达在多领域有重要的应用价值,大肠杆菌共表达系统包括多顺反子系统和双质粒系统,两者各有优缺点。多顺反子系统不需外界2种抗生素的同时存在,但操作较为复杂。通常认为,具有相同复制子的质粒是不相容的,但近来的实验表明,在双抗生素的选择压力下,不相容的双质粒系统也能稳定传代,且操作简单,周期较短。双质粒系统已经应用于生产、医学等各个领域。

The Strategy of Coexpression in Escherichia coli

Coexpression of genes has showed its important value in many domains.There are mainly two strategies to coexpress proteins in E.coli.One is to use a bicistronic vector,which is generated by cloning two target genes into one plasmid.The other strategy relies on the two-plasmid coexpression system in which foreign genes are cloned in two different vectors.The first strategy is no need for existence of two antibiotics,but it is more complex than the second one.It has been considered that the two plasmids having the same replicon are incompatibility,but the resent experiments show that two plasmids carrying the same replicon can still coexist in E.coli,if under the selection pressure of two antibiotics,so the second one is more simple and convenient than the first one.Now the two-plasmid coexpression system is applied to many domains,such as production,the science of diagnosing,treating,or preventing disease.