过表达S-腺苷甲硫氨酸合成酶及优化碳源高产洛蒙真菌素  

Enhanced Biosynthesis of Lomofungin via Overexpressing S-Adenosy Imethionine Synthetase and Optimizing Carbon Source

作　　者：邓如祥 王威[1] 张雪洪[1] Deng Ruxiang;Wang Wei;Zhang Xuehong(State Key Laboratory of Microbial Metabolism,School of Life Science and Biotechnology,Shanghai Jiao Tong University,Shanghai,200240)

机构地区：[1]上海交通大学生命科学技术学院,微生物代谢国家重点实验室,上海200240

出　　处：《基因组学与应用生物学》2021年第4期1618-1625,共8页Genomics and Applied Biology

基　　金：上海市自然科学基金项目(16ZR1416700);生物基材料与绿色造纸国家重点实验室开放基金资助项目(KF201822);国家重点研发计划项目(2019YFA0904302)共同资助。

摘　　要：洛蒙真菌素是由洛蒙德链霉菌S015合成的天然吩嗪类化合物,该化合物具有广谱抑菌活性及抗肿瘤活性,但因其在野生菌株中的产量较低而限制了应用。为了提高洛蒙真菌素产量,探究相关基因功能及S015菌株发酵条件,本研究首先建立系统进化树分析内源S-腺苷甲硫氨酸合成酶MetK,其次在野生型S015中过表达metK基因,最后通过动态发酵实验进行碳源优化。研究结果表明,过表达metK基因的菌株洛蒙真菌素产量达到(27.4±2.8) mg/L,是野生株的2.3倍;通过发酵优化,以20 g/L的木糖为碳源时洛蒙真菌素产量最高,为(130.6±8.0) mg/L,是优化前的4.8倍。本研究成功采用上游基因工程改造结合下游发酵优化的生物工程手段,有效地提高了菌株S015中洛蒙真菌素的产量。Lomofungin, generally biosynthesized by Streptomyces lomondensis S015, is a kind of phenazine compound which has broad-spectrum antifungal, antibacterial, and antitumor activities. The low-level production of lomofungin in S015 wild-type strain has been a limitation for its widely application. In order to improve the production of lomofungin and explore the function of related genes and fermentation conditions of S015 strain, this study first established a phylogenetic tree to analyze the endogenous S-adenosylmethionine synthetase metk, then overexpressed metK gene in wild-type S015, and finally optimized the carbon source through dynamic fermentation ex periment. The results showed that the production of lomofungin reached(27.4±2.8) mg/L by overexpressing metK gene, about 2.3-fold higher than that in wild-type S015. Carbon source optimization showed that the highest lomofungin production(130.6±8.0) mg/L was obtained while using 20 g/L xylose, increasing about 4.8-fold compared with the unoptimized condition. This study took advantage of up-stream gene manipulation and down-stream fermentation optimization strategy, significantly enhanced the production of lomofungin.

关 键 词：洛蒙真菌素 S-腺苷甲硫氨酸合成酶基因metK 基因过表达 发酵优化 

分 类 号：TQ929[轻工技术与工程—发酵工程] O629[理学—有机化学]