Raising the production of phloretin by alleviation of by-product of chalcone synthase in the engineered yeast  

作　　者：Chunmei Jiang Xiaonan Liu Xianqing Chen Yi Cai Yibin Zhuang Tian Liu Xiaoxi Zhu Hui Wang Yuwan Liu Huifeng Jiang Wen Wang 

机构地区：[1]Key Laboratory for Space Bioscience and Space Biotechnology,School of Life Sciences,Northwestern Polytechnical University,Xi’an 710072,China [2]Key Laboratory of Systems Microbial Biotechnology,Tianjin Institute of Industrial Biotechnology,Chinese Academy of Sciences,Tianjin 300308,China [3]University of Chinese Academy of Sciences,Beijing 100049,China [4]Center for Ecology and Environmental Sciences,Northwestern Polytechnical University,Xi’an 710072,China [5]Jiaxing Synbiolab Biotechnology Co.,Ltd.,Jiaxing 314006,China

出　　处：《Science China(Life Sciences)》2020年第11期1734-1743,共10页中国科学（生命科学英文版）

基　　金：financially supported by Talents Team Construction Fund of Northwestern Polytechnical University (NWPU);the National Natural Science Foundation of China (31701722);the China Postdoctoral Science Foundation (2017M620471);the National Natural Science Foundation of China (31901026)。

摘　　要：Phloretin is an important skin-lightening and depigmenting agent from the peel of apples. Although de novo production of phloretin has been realized in microbes using the natural pathway from plants, the efficiency of phloretin production is still not enough for industrial application. Here, we established an artificial pathway in the yeast to produce phloretin via assembling two genes of p-coumaroyl-CoA ligase(4CL) and chalcone synthase(CHS). CHS is a key enzyme which conventionally condenses a CoA-tethered starter with three molecules of malonyl-CoA to form the backbone of flavonoids. However, there was 33% of byproduct generated via CHS by condensing two molecules of malonyl-CoA during the fermentation process. Hence, we introduced a more efficient CHS and improved the supply of malonyl-CoA through two pathways;the by-product ratio was decreased from 33% to 17% and the production of phloretin was improved from 48 to 83.2 mg L^(-1). Finally, a fed-batch fermentation process was optimized and the production of phloretin reached 619.5 mg L^(-1), which was 14-fold higher than that of the previous studies. Our work established a platform for the biosynthesis of phloretin from the low-cost raw material 3-(4-hydroxyphenyl) propanoic acid and also illustrated the potential for industrial scale bio-manufacturing of phloretin.

关 键 词：PHLORETIN Saccharomyces cerevisiae metabolic engineering microbial cell factories fed-batch fermentation 

分 类 号：TQ920.1[轻工技术与工程—发酵工程]