Predictability and robustness are challenges for bioproduction because of the unstable intracellular synthetic activities. With the deeper understanding of the gene expression process, fine-tuning has become a meaningful tool for biosynthesis optimization. This study characterized several gene expression elements and constructed a multiple inducible system that responds to ten different small chemical inducers in halophile bacterium Halomonas bluephagenesis. Genome insertion of regulators was conducted for the purpose of gene cluster stabilization and regulatory plasmid simplification. Additionally, dynamic ranges of the multiple inducible systems were tuned by promoter sequence mutations to achieve diverse scopes for high-resolution gene expression control. The multiple inducible system was successfully employed to precisely control chromoprotein expression, lycopene and poly-3-hydroxybutyrate (PHB) biosynthesis, resulting in colorful bacterial pictures, optimized cell growth, lycopene and PHB accumulation. This study demonstrates a desirable approach for fine-tuning of rational and efficient gene expressions, displaying the significance for metabolic pathway optimization.

由于细胞内合成活动不稳定，可预测性和鲁棒性是生物生产面临的挑战。随着对基因表达过程的深入了解，微调已成为生物合成优化的有意义的工具。这项研究表征了几种基因表达元件，并构建了一个多重诱导系统，该系统对嗜盐细菌蓝色嗜盐单胞菌发生中的十种不同的小化学诱导剂作出反应。进行调节子的基因组插入是为了基因簇稳定和调节质粒简化。此外，通过启动子序列突变调整多个诱导系统的动态范围，以实现高分辨率基因表达控制的不同范围。多重诱导系统成功地用于精确控制色蛋白表达、番茄红素和聚 3-羟基丁酸酯 (PHB) 生物合成，从而产生丰富多彩的细菌图片、优化细胞生长、番茄红素和 PHB 积累。这项研究展示了一种合理有效的基因表达微调的理想方法，对代谢途径优化具有重要意义。