Sunscreen has been used for thousands of years to protect skin from ultraviolet radiation. However, the use of modern commercial sunscreen containing oxybenzone, ZnO, and TiO has raised concerns due to their negative effects on human health and the environment. In this study, we aim to establish an efficient microbial platform for production of shinorine, a UV light absorbing compound with anti-aging properties. First, we methodically selected an appropriate host for shinorine production by analyzing central carbon flux distribution data from prior studies alongside predictions from genome-scale metabolic models (GEMs). We enhanced shinorine productivity through CRISPRi-mediated downregulation and utilized shotgun proteomics to pinpoint potential competing pathways. Simultaneously, we improved the shinorine biosynthetic pathway by refining its design, optimizing promoter usage, and altering the strength of ribosome binding sites. Finally, we conducted amino acid feeding experiments under various conditions to identify the key limiting factors in shinorine production. The study combines meta-analysis of C-metabolic flux analysis, GEMs, synthetic biology, CRISPRi-mediated gene downregulation, and omics analysis to improve shinorine production, demonstrating the potential of KT2440 as platform for shinorine production.

中文翻译：

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恶臭假单胞菌生产抗衰老防晒化合物的系统工程


防晒霜用于保护皮肤免受紫外线辐射已有数千年的历史。然而，含有氧苯酮、氧化锌和二氧化钛的现代商业防晒霜的使用因其对人类健康和环境的负面影响而引起了人们的关注。在这项研究中，我们的目标是建立一个有效的微生物平台来生产 shinorine，一种具有抗衰老特性的紫外线吸收化合物。首先，我们通过分析先前研究的中心碳通量分布数据以及基因组规模代谢模型（GEM）的预测，系统地选择了合适的 shinorine 生产宿主。我们通过 CRISPRi 介导的下调提高 shinorine 生产力，并利用鸟枪蛋白质组学来查明潜在的竞争途径。同时，我们通过改进设计、优化启动子使用和改变核糖体结合位点的强度来改进 shinorine 生物合成途径。最后，我们在不同条件下进行了氨基酸饲喂实验，以确定 shinorine 生产的关键限制因素。该研究结合了 C 代谢流分析、GEM、合成生物学、CRISPRi 介导的基因下调和组学分析的荟萃分析来提高 shinorine 产量，证明了 KT2440 作为 shinorine 生产平台的潜力。