Joint BioEnergy Institute, Emeryville, CA, 94608, USA.
Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
Commun Biol. 2022 Dec 12;5(1):1363. doi: 10.1038/s42003-022-04336-2.
Despite advances in understanding the metabolism of Pseudomonas putida KT2440, a promising bacterial host for producing valuable chemicals from plant-derived feedstocks, a strain capable of producing free fatty acid-derived chemicals has not been developed. Guided by functional genomics, we engineered P. putida to produce medium- and long-chain free fatty acids (FFAs) to titers of up to 670 mg/L. Additionally, by taking advantage of the varying substrate preferences of paralogous native fatty acyl-CoA ligases, we employed a strategy to control FFA chain length that resulted in a P. putida strain specialized in producing medium-chain FFAs. Finally, we demonstrate the production of oleochemicals in these strains by synthesizing medium-chain fatty acid methyl esters, compounds useful as biodiesel blending agents, in various media including sorghum hydrolysate at titers greater than 300 mg/L. This work paves the road to produce high-value oleochemicals and biofuels from cheap feedstocks, such as plant biomass, using this host.
尽管人们对 Pseudomonas putida KT2440 的代谢有了更深入的了解，该菌是一种很有前途的细菌宿主，可用于从植物原料中生产有价值的化学品，但目前仍未开发出能够生产游离脂肪酸衍生化学品的菌株。本研究以功能基因组学为指导，对 P. putida 进行了工程改造，使其能够生产中链和长链游离脂肪酸（FFAs），最高产量可达 670mg/L。此外，我们还利用同源脂肪酸酰基辅酶 A 连接酶的不同底物偏好，采用了一种控制 FFA 链长的策略，使 P. putida 菌株专门用于生产中链 FFAs。最后，我们通过在不同的培养基中（包括高粱水解物）合成中链脂肪酸甲酯，展示了这些菌株在这些菌株中的生产能力，这些化合物可用作生物柴油的混合剂，产量大于 300mg/L。这项工作为利用这种宿主从廉价原料（如植物生物质）生产高价值的油脂化学品和生物燃料铺平了道路。
