Streptomyces spp. are “nature’s antibiotic factories” that produce valuable bioactive metabolites, such as the cytotoxic anthracycline polyketides. While the anthracyclines have hundreds of natural and chemically synthesized analogues, much of the chemical diversity stems from enzymatic modifications to the saccharide chains and, to a lesser extent, from alterations to the core scaffold. Previous work has resulted in the generation of a BioBricks synthetic biology toolbox in Streptomyces coelicolor M1152ΔmatAB that could produce aklavinone, 9-epi-aklavinone, auramycinone, and nogalamycinone. In this work, we extended the platform to generate oxidatively modified analogues via two crucial strategies. (i) We swapped the ketoreductase and first-ring cyclase enzymes for the aromatase cyclase from the mithramycin biosynthetic pathway in our polyketide synthase (PKS) cassettes to generate 2-hydroxylated analogues. (ii) Next, we engineered several multioxygenase cassettes to catalyze 11-hydroxylation, 1-hydroxylation, 10-hydroxylation, 10-decarboxylation, and 4-hydroxyl regioisomerization. We also developed improved plasmid vectors and S. coelicolor M1152ΔmatAB expression hosts to produce anthracyclinones. This work sets the stage for the combinatorial biosynthesis of bespoke anthracyclines using recombinant Streptomyces spp. hosts.

中文翻译：

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蒽环酮 C-H 功能化的多种组合生物合成策略

链霉菌属是“大自然的抗生素工厂”，可生产有价值的生物活性代谢物，例如细胞毒性蒽环类聚酮化合物。虽然蒽环类药物有数百种天然和化学合成的类似物，但大部分化学多样性源于对糖链的酶促修饰，以及在较小程度上源于对核心支架的改变。之前的工作已经在天蓝色链霉菌M1152Δ matAB中生成了 BioBricks 合成生物学工具箱，可以产生阿克拉维酮、9-表-阿克拉维酮、金霉素酮和诺加霉素酮。在这项工作中，我们扩展了平台，通过两种关键策略生成氧化修饰类似物。 (i) 我们将聚酮合酶 (PKS) 盒中光神霉素生物合成途径中的芳香酶环化酶替换为酮还原酶和一环环化酶，以生成 2-羟基化类似物。 (ii)接下来，我们设计了几种多加氧酶盒来催化11-羟基化、1-羟基化、10-羟基化、10-脱羧和4-羟基区域异构化。我们还开发了改进的质粒载体和S. coelicolor M1152Δ matAB表达宿主来生产蒽环类化合物。这项工作为使用重组链霉菌属的定制蒽环类药物的组合生物合成奠定了基础。主机。