工程改造龟裂链霉菌提高土霉素产量  

Engineering Strategies for Improved the Oxytetracycline Production in Streptomyces rimosus

作　　者：尹守亮[1] 林智炜 张玉秀[1] 王为善[2] 史明欣[2] 杨克迁[2] 

机构地区：[1]中国矿业大学(北京)化学与环境工程学院环境与生物工程系,北京100083 [2]中国科学院微生物研究所微生物资源前期开发国家重点实验室,北京100101

出　　处：《中国生物工程杂志》2016年第7期72-82,共11页China Biotechnology

基　　金：国家自然科学基金(31130001);中国矿业大学(北京)中央高校基本科研业务费专项基金(2010YH05);国家大学生创新训练项目(C201503043)资助项目

摘　　要：土霉素是由龟裂链霉菌合成的一类广谱性抗生素,前期研究工作证明其生物合成受其自身途径特异性调控蛋白OtcR的直接调节,OtcR能够激活和促进土霉素合成基因簇的转录表达。在龟裂链霉菌M4018宿主内利用强启动子单独过表达OtcR蛋白,使土霉素的产量提高到原来产量的4倍;为了进一步提高土霉素产量,在M4108宿主内表达乙酰辅酶A羧化酶基因,提高其胞内土霉素合成的前体物丙二酸单酰辅酶A的含量。对出发菌株M4018进行工程改造,同时过表达途径特异性调控蛋白OtcR和乙酰辅酶A羧化酶,发酵检测改造后的重组工程菌株土霉素的产量由1.37g/L提高到9.09g/L,该研究策略对工程改造龟裂链霉菌提高土霉素的产量具有重要的指导意义。Oxytetracycline（ OTC） is a broad-spectrum antibiotic produced by Streptomyces rimosus. OtcR was confirmed to be the pathway-specific activator of OTC biosynthesis to directly activate the oxy（ oxytetracycline） cluster. OTC production was significantly improved by overexpression of OtcR under the strong promoters. Overexpression of OtcR increased OTC production dramatically by 4 times compared to the parental strain S. rimosus M4018. For a further improvement of the OTC production,the intracellular pool of malonyl-Co A by overexpressing acetyl-Co A carboxylase in M4018 were increased. Herein,for the OTC production,that by overexpressing both the pathway-specific activator OtcR and acetyl-Co A carboxylase in S. rimosus had been shown,a maximum of 9. 09 g / L was achieved in recombination strains,while only 1. 37 g / L in the wild type strain M4018. The work has an important significance for engineering industrial strains to improve OTC production.

关 键 词：土霉素 龟裂链霉菌 途径特异性调控蛋白OtcR乙酰辅酶A羧化酶 工程改造 

分 类 号：Q81[生物学—生物工程] Q78