DepR1, a TetR Family Transcriptional Regulator, Positively Regulates Daptomycin Production in an Industrial Producer, Streptomyces roseosporus SW0702
DepR1, a TetR Family Transcriptional Regulator, Positively Regulates Daptomycin Production in an Industrial Producer, Streptomyces roseosporus SW0702
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DOI：
10.1128/aem.03002-15
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发表时间：
2016-01
影响因子：
4.4
通讯作者：
Peng-Hui Yuan;Ri-Cheng Zhou;Xuepeng Chen;Shuai Luo;Feng Wang;X. Mao;Yong-Quan Li
中科院分区：
文献类型：
--
作者：
Peng-Hui Yuan;Ri-Cheng Zhou;Xuepeng Chen;Shuai Luo;Feng Wang;X. Mao;Yong-Quan Li
达托霉素是一种有效的环脂肽类抗生素。它被广泛用于对抗各种革兰氏阳性细菌病原体。从历史上看，对达托霉素生物合成的转录调控的理解不足，限制了针对效价提高的靶向基因工程的选择。在这里，我们分离TetR家族的转录调节因子，DepR1，从工业生产链霉菌roseosporus SW 0702使用生物素化dptE启动子（dptEp）作为探针。然后通过电泳迁移率变动分析和DNA酶I足迹分析证实DepR1和dptEp之间的直接相互作用。depR1的缺失导致dptEp活性的降低和达托霉素生产的停止。ΔdepR1突变株在R5培养基上产红色素较少，不能产孢。这表明DepR1在形态分化的控制中起着积极的作用。此外，DepR1通过直接结合其自身启动子而被正向自身调节。这可能解释了达托霉素生产的正反馈调节。基于这些积极的影响，通过过量表达depR1的基因工程提高了达托霉素的产量，并缩短了摇瓶和发酵罐中的发酵周期。
ABSTRACT Daptomycin is a potent cyclic lipopeptide antibiotic. It is widely used against various Gram-positive bacterial pathogens. Historically, a poor understanding of the transcriptional regulation of daptomycin biosynthesis has limited the options for targeted genetic engineering toward titer improvement. Here, we isolated a TetR family transcriptional regulator, DepR1, from the industrial producer Streptomyces roseosporus SW0702 using a biotinylated dptE promoter (dptEp) as a probe. The direct interaction between DepR1 and dptEp then was confirmed by electrophoretic mobility shift assays and DNase I footprinting assays. The deletion of depR1 led to a reduction in dptEp activity and the cessation of daptomycin production. The ΔdepR1 mutant produced less red pigment and failed to sporulate on R5 medium. This suggests that DepR1 plays a positive role in the control of morphological differentiation. Moreover, DepR1 was positively autoregulated by directly binding to its own promoter. This might account for the positive feedback regulation of daptomycin production. Based on these positive effects, genetic engineering by overexpression of depR1 raised daptomycin production and shortened the fermentation period both in flask and in fermentor.