An Autoregulated Fine-Tuning Strategy for Titer Improvement of Secondary Metabolites Using Native Promoters in Streptomyces
An Autoregulated Fine-Tuning Strategy for Titer Improvement of Secondary Metabolites Using Native Promoters in Streptomyces
复制标题
使用链霉菌天然启动子提高次级代谢产物滴度的自动调节微调策略
DOI：
10.1021/acssynbio.7b00318
复制
发表时间：
2018-02-01
影响因子：
4.7
通讯作者：
Wang, Weishan
中科院分区：
文献类型：
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作者：
Li, Shanshan;Wang, Junyang;Wang, Weishan
链霉菌是众所周知的生物活性次生代谢产物的生产者。人们已经做出了各种努力来增加这些代谢物的产量，但很少有方法可以很好地协调次级代谢物的生物合成及其宿主的其他生理事件。在这里，我们开发了一种通用的自动调节策略，用于微调链霉菌属次生代谢物生物合成基因簇（BGC）的表达。首先，诱导型启动子用于控制次级代谢产物 BGC 的表达。然后，通过响应面模型从时间和强度两个维度确定最佳诱导条件。最后，基于时程转录组分析，鉴定出在最佳条件下与诱导型启动子具有相似转录特征的天然启动子，并通过精心设计的替换方法用于替换诱导型启动子。使用该策略优化了天蓝色链霉菌中放线菌紫素 (Act) 和异源土霉素 (OTC) BGC 的表达。与通过组成型启动子调节表达相比，我们的策略可以将 Act 和 OTC 的效价分别显着提高 1.3 倍和 9.1 倍。这里开发的自动调节微调策略为链霉菌中所需次级代谢产物的滴度提高开辟了一条新途径。
Streptomycetes are well-known producers of biologically active secondary metabolites. Various efforts have been made to increase productions of these metabolites, while few approaches could well coordinate the biosynthesis of secondary metabolites and other physiological events of their hosts. Here we develop a universal autoregulated strategy for fine-tuning the expression of secondary metabolites biosynthetic gene clusters (BGCs) in Streptomyces species. First, inducible promoters were used to control the expression of secondary metabolites BGCs. Then, the optimal induction condition was determined by response surface model in both dimensions of time and strength. Finally, native promoters with similar transcription profile to the inducible promoter under the optimal condition were identified based on time-course transcriptome analyses, and used to replace the inducible promoter following an elaborate replacement approach. The expression of actinorhodin (Act) and heterogeneous oxytetracycline (OTC) BGCs were optimized in Streptomyces coelicolor using this strategy. Compared to modulating the expression via constitutive promoters, our strategy could dramatically improve the titers of Act and OTC by 1.3- and 9.1-fold, respectively. The autoregulated fine-tuning strategy developed here opens a novel route for titer improvement of desired secondary metabolites in Streptomyces.