School of Environmental Engineering, University of Seoul, Seoul 02504, Republic of Korea.
World Institute of Kimchi, Gwangju 61755, Republic of Korea.
J Agric Food Chem. 2020 May 6;68(18):5147-5153. doi: 10.1021/acs.jafc.0c01024. Epub 2020 Apr 21.
Developing a highly efficient and ecofriendly system to produce desired products from waste can be considered important to a sustainable society. Here, we report for the first time high-yield production of lycopene through metabolically engineering an extremophilic microorganism, R1, from corn steep liquor (CSL) and glycerol. First, the gene-encoding lycopene cyclase was deleted to prevent the conversion of lycopene to γ-carotene. Then, the gene-encoding phytoene synthase and the gene-encoding 1-deoxy-d-xylulose 5-phosphate synthase were overexpressed to increase carbon flux toward lycopene. The engineered Δ/ R1 could produce 273.8 mg/L [80.7 mg/g dry cell weight (DCW)] and 373.5 mg/L (108.0 mg/g DCW) of lycopene from 10 g/L of glucose with 5 g/L of yeast extract and 9.9 g/L of glucose with 20 g/L of CSL, respectively. Moreover, the lycopene titer and content were increased by 26% (470.6 mg/L) and 28% (138.2 mg/g DCW), respectively, when the carbon source was changed to glycerol. Finally, fed-batch fermentation of the final engineered strain allowed the production of 722.2 mg/L (203.5 mg/g DCW) of lycopene with a yield and productivity of 20.3 mg/g glycerol and 6.0 mg/L/h, respectively, from 25 g/L of CSL and 35.7 g/L of glycerol.
开发高效、环保的系统，从废物中生产所需的产品，可以被认为对可持续社会很重要。在这里，我们首次报道了通过代谢工程化一种极端微生物 R1，从玉米浆（CSL）和甘油中高产生产番茄红素。首先，删除编码番茄红素环化酶的基因，以防止番茄红素转化为γ-胡萝卜素。然后，过表达编码八氢番茄红素合酶的基因和编码 1-脱氧-d-木酮糖 5-磷酸合酶的基因，以增加番茄红素的碳通量。工程菌Δ/ R1 可以从 10 g/L 葡萄糖中分别以 5 g/L 酵母提取物和 9.9 g/L 葡萄糖和 20 g/L CSL 为碳源生产 273.8 mg/L[80.7 mg/g 干细胞重量（DCW）]和 373.5 mg/L（108.0 mg/g DCW）的番茄红素。此外，当碳源变为甘油时，番茄红素的产量和含量分别提高了 26%（470.6 mg/L）和 28%（138.2 mg/g DCW）。最后，对最终工程菌进行分批补料发酵，从 25 g/L CSL 和 35.7 g/L 甘油中生产出 722.2 mg/L（203.5 mg/g DCW）的番茄红素，产率和生产率分别为 20.3 mg/g 甘油和 6.0 mg/L/h。
