We present a Penicillium rubens strain with an industrial background in which the four highly expressed biosynthetic gene clusters (BGC) required to produce penicillin, roquefortine, chrysogine and fungisporin were removed. This resulted in a minimal secondary metabolite background. Amino acid pools under steady-state growth conditions showed reduced levels of methionine and increased intracellular aromatic amino acids. Expression profiling of remaining BGC core genes and untargeted mass spectrometry did not identify products from uncharacterized BGCs. This platform strain was repurposed for expression of the recently identified polyketide calbistrin gene cluster and achieved high yields of decumbenone A, B and C. The penicillin BGC could be restored through in vivo assembly with eight DNA segments with short overlaps. Our study paves the way for fast combinatorial assembly and expression of biosynthetic pathways in a fungal strain with low endogenous secondary metabolite burden.

中文翻译：

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用于次生代谢产物的青霉青霉平台菌株

我们提出了具有工业背景的青霉青霉菌株，其中去除了生产青霉素，罗克福汀，金霉素和真菌孢子素所需的四个高度表达的生物合成基因簇（BGC）。这导致最小的次生代谢产物背景。稳态生长条件下的氨基酸库显示降低的蛋氨酸水平和增加的细胞内芳族氨基酸。其余BGC核心基因的表达谱分析和非靶向质谱分析未鉴定未鉴定BGC的产物。该平台菌株被重新用于表达最近鉴定的聚酮化合物calbistrin基因簇，并获得了高产率的癸二烯酮A，B和C。青霉素BGC可通过体内恢复带有短重叠的八个DNA片段的组装。我们的研究为在具有低内源性次生代谢产物负担的真菌菌株中快速组合组装和生物合成途径的表达铺平了道路。