基因重组法构建表柔红霉素高产菌株

Construction of a high epidaunorubicin-producing strain by gene recombination

摘要: 表柔红霉素是抗肿瘤药表阿霉素的半合成前体。通过中断dnmV基因，并将酮基还原酶aveBⅥ基因导入，可以将柔红霉素产生菌改造成表柔红霉素产生菌。本研究通过此方法得到了产表柔红霉素的基因工程菌mHJ-02-30-1，在此基础上构建柔红霉素生物合成基因dnrU的同框敲除质粒pYG1116，将其转入原有的表柔红霉素产生菌mHJ-02-30-1，通过同源重组双交换的方法，将dnrU基因内部编码153个氨基酸的序列敲除。从而得到dnrU基因失活的突变株mYG1116E，发酵验证表明该突变株表柔红霉素发酵单位比出发菌株提高了约40%。

Abstract: 4′-Epidaunorubicin is major precursor for the semisynthesis of epidoxorubicin，a clinically important antitumor antibiotic.By means of homologous recombination used for dnmV replacement and aveBⅣ integration into daunorubicin-producing strain，a mutant strain，named mHJ-02-30-1，was obtained that produces 4′-epidaunorubin.An in-frame knock-out plasmid was transformed into mHJ-02-30-1 to delete the dnrU gene fragment encoding 153 amino acids.The genetic engineering strain mYG1116E，a dnrU gene inactivation mutant，was constructed by homologous recombination，which increased the 4′-epidaunorubin production by 40% compared with the original strain.