产紫杉醇真菌Pestalotiopsis microspora NK17适合遗传筛选的培养基优化

小孢拟盘多毛孢菌株NK17被证明能够产生多种具有药物开发价值的紫杉烷类似物以及冠心病治疗药物的前导物pestalotiollide B等次级代谢产物。由于是天然分离的菌株,该菌的营养要求未知,特别是缺少合适的全合成基础培养基,制约了实验室对其性状和基因水平的操作。尤其是在使用营养缺陷型菌株进行遗传转化时,全合成基础培养基是筛选工作的前提。对各种基础培养基进行筛选比较,最终确定酵母氮源加乳糖和硫酸铵的全合成基础培养基最适合NK17菌丝生长和营养缺陷型筛选。同时对该培养基的发酵产物进行了研究,成功应用该培养基进行了缺陷型回补筛选,效果较好。

Medium Optimization Suitable for Genetic Screening of Taxol-Producing Fungus Pestalotiopsis microspora NK17

Pestalotiopsis microspora NK17 has been proved could produce many useful secondary metabolites that possesses values in medicine development, including parallel of yew alkane as well as preceding substance for coronary treatment, paclitaxel and pestalotiollide B etc. Since the nutritional requirement of the strain remains unknown, and the lack of an appropriate totally synthetic minimal medium, these have limited the genetic manipulation in its characters and genetic levels. Especially a totally synthetic basic medium is the key prerequisite for screening works when using auxotrophic strains to carry out genetic transformation. In this study, the growth of NK17 on several minimal media and their improved versions were screened and compared. A totally synthetic minimal medium with yeast nitrogen source plus lactose and (NH₄)₂SO₄ was finally confirmed to be the most suitable for NK17 mycelial growth and screening for auxotroph. At the same time, the fermentation products of were studied, and successfully retro-mend screened the auxotroph using the medium with fairly good effects.