A bimodular PKS platform that expands the biological design space.
A bimodular PKS platform that expands the biological design space.
复制标题
扩展生物设计空间的双模块 PKS 平台。
DOI：
10.1016/j.ymben.2020.07.001
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发表时间：
2020
影响因子：
8.4
通讯作者：
Keasling,JayD
中科院分区：
文献类型：
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作者：
Zargar,Amin;Valencia,Luis;Wang,Jessica;Lal,Ravi;Chang,Samantha;Werts,Miranda;Wong,AndrewR;Hernández,AmandaC;Benites,Veronica;Baidoo,EdwardEK;Katz,Leonard;Keasling,JayD
I型模块化聚酮酶（PKS）传统上被工程化以产生新的生物活性分子，可以被工程化作为用于生产新型燃料、商品化学品和特种化学品的新的生物合成平台。以前，我们的研究操纵的第一个模块的脂霉素PKS产生短链酮，3-羟基酸，饱和，支链羧酸。在这项工作的基础上，我们已经扩展到多模块系统，通过工程化的前两个模块的脂霉素产生非天然的聚酮化合物作为潜在的生物燃料和特殊化学品在白色链霉菌。首先，我们通过LipPKS 1中的还原环交换和LipPKS 2中的酮还原酶敲除产生20.6 mg/L的乙基酮、4，6二甲基庚酮。然后，我们表明，在LipPKS 1的AT交换和LipPKS 2的还原环交换可以产生潜在的香料3-异丙基-6-甲基四氢吡喃酮。突出了保持产品保真度的挑战，在两个双模块系统中，我们观察到来自工程化的第一模块中的过早水解的副产物和还原性环交换中的停滞脱水。总的来说，我们的工作扩展了生物设计空间，并使该领域更接近于“设计师”生物分子的生产。
Traditionally engineered to produce novel bioactive molecules, Type I modular polyketide synthases (PKSs) could be engineered as a new biosynthetic platform for the production ofde novofuels, commodity chemicals, and specialty chemicals. Previously, our investigations manipulated the first module of the lipomycin PKS to produce short chain ketones, 3-hydroxy acids, and saturated, branched carboxylic acids. Building upon this work, we have expanded to multi-modular systems by engineering the first two modules of lipomycin to generate unnatural polyketides as potential biofuels and specialty chemicals in Streptomyces albus. First, we produce 20.6 mg/L of the ethyl ketone, 4,6 dimethylheptanone through a reductive loop exchange in LipPKS1 and a ketoreductase knockouts in LipPKS2. We then show that an AT swap in LipPKS1 and a reductive loop exchange in LipPKS2 can produce the potential fragrance 3-isopropyl-6-methyltetrahydropyranone. Highlighting the challenge of maintaining product fidelity, in both bimodular systems we observed side products from premature hydrolysis in the engineered first module and stalled dehydration in reductive loop exchanges. Collectively, our work expands the biological design space and moves the field closer to the production of “designer” biomolecules.