Department of Biotechnology, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
Commun Biol. 2024 Oct 4;7(1):1263. doi: 10.1038/s42003-024-06958-0.
Natural secondary metabolites are medically, agriculturally, and industrially beneficial to humans. For mass production, a heterologous production system is required, and various metabolic engineering trials have been reported in Escherichia coli and Saccharomyces cerevisiae to increase their production levels. Recently, filamentous fungi, especially Aspergillus oryzae, have been expected to be excellent hosts for the heterologous production of natural products; however, large-scale metabolic engineering has hardly been reported. Here, we elucidated candidate metabolic pathways to be modified for increased model terpene production by RNA-seq and metabolome analyses in A. oryzae and selected pathways such as ethanol fermentation, cytosolic acetyl-CoA production from citrate, and the mevalonate pathway. We performed metabolic modifications targeting these pathways using CRISPR/Cas9 genome editing and demonstrated their effectiveness in heterologous terpene production. Finally, a strain containing 13 metabolic modifications was generated, which showed enhanced heterologous production of pleuromutilin (8.5-fold), aphidicolin (65.6-fold), and ophiobolin C (28.5-fold) compared to the unmodified A. oryzae strain. Therefore, the strain generated by engineering multiple metabolic pathways can be employed as a versatile highly-producing host for a wide variety of terpenes.
天然次生代谢产物对人类具有医学、农业和工业价值。为了进行大规模生产,需要一个异源生产系统,并且已经在大肠杆菌和酿酒酵母中报告了各种代谢工程试验,以提高它们的生产水平。最近,丝状真菌,特别是米曲霉,被期望成为天然产物异源生产的优秀宿主;然而,几乎没有报道大规模的代谢工程。在这里,我们通过 RNA-seq 和米曲霉的代谢组分析阐明了候选代谢途径,以增加模型萜烯的产量,并选择了乙醇发酵、柠檬酸细胞质乙酰辅酶 A 生产和甲羟戊酸途径等途径。我们使用 CRISPR/Cas9 基因组编辑针对这些途径进行了代谢修饰,并证明了它们在异源萜烯生产中的有效性。最后,生成了一个包含 13 种代谢修饰的菌株,与未修饰的米曲霉菌株相比,该菌株增强了pleuromutilin(8.5 倍)、aphidicolin(65.6 倍)和ophiobolin C(28.5 倍)的异源生产。因此,通过工程化多个代谢途径生成的菌株可以用作各种萜烯的通用高产生物宿主。