对菌株 Y-2维生素 K2合成途径中的6个主要酶基因分别进行克隆和表达，以探索不同酶基因对 MK-7产量的影响。参照《分子克隆实验指南》完成对基因重组质粒的构建，并对 spizizen 转化法进行改进，实现重组质粒对菌株 Y-2的转化。结果表明，分别过量表达维生素 K2合成途径中的6个基因均能提高 MK-7的产量。需要指出的是，过表达基因 hep S 对 MK-7产量的影响最大，其中在摇瓶培养组的产量提高了38%，静置培养组的产量提高了48%。其余几个基因过表达后对 MK-7产量的影响则根据培养方式的不同而各有差异。%This paper focused on understanding the effects of different enzyme genes on MK-7 production by cloning and expressing the genes of 6 enzymes in the biosynthetic pathway of vitamin K2 with strain Y-2. Firstly,the recombinant plasmids with single gene of the 6 genes were constructed according to the description of Guide to Molecular Cloning Experiment. Subsequently,the recombinant plasmids were successfully transformed into the strain Y-2 via the improved“spizizen”transformation method. Results showed that respective overexpression of the 6 genes involved in vitamin K2 biosynthetic pathway all was beneficial to raise MK-7 production. It should be noted that overexpression of gene hep S had the greatest effects on MK-7 production among these 6 genes,which resulted in an increase by 38% in shaking group and by 48% in static group. However,the effects of other genes on MK-7 production varied depending on the culture mode.
展开▼
