Increased Cordycepin Production in Yarrowia lipolytica Using Combinatorial Metabolic Engineering Strategies.

As the first nucleoside antibiotic discovered in fungi, cordycepin, with its various biological activities, has wide applications. At present, cordycepin is mainly obtained from the natural fruiting bodies of Cordyceps militaris. However, due to long production periods, low yields, and low extraction efficiency, harvesting cordycepin from natural C. militaris is not ideal, making it difficult to meet market demands. In this study, an engineered Yarrowia lipolytica YlCor-18 strain, constructed by combining metabolic engineering strategies, achieved efficient de novo cordycepin production from glucose. First, the cordycepin biosynthetic pathway derived from C. militaris was introduced into Y. lipolytica. Furthermore, metabolic engineering strategies including promoter, protein, adenosine triphosphate, and precursor engineering were combined to enhance the synthetic ability of engineered strains of cordycepin. Fermentation conditions were also optimized, after which, the production titer and yields of cordycepin in the engineered strain YlCor-18 under fed-batch fermentation were improved to 4362.54 mg/L and 213.85 mg/g, respectively, after 168 h. This study demonstrates the potential of Y. lipolytica as a cell factory for cordycepin synthesis, which will serve as the model for the green biomanufacturing of other nucleoside antibiotics using artificial cell factories.

High-level de novo biosynthesis of cordycepin by systems metabolic engineering in Yarrowia lipolytica.

Cordycepin is a nucleoside antibiotic with various biological activities, which has wide applications in the area of cosmetic and medicine industries. However, the current production of cordycepin is costly and time-consuming. To construct the promising cell factory for high-level cordycepin production, firstly, the design and construction of cordycepin biosynthetic pathway were performed in Yarrowia lipolytica. Secondly, the adaptivity between cordycepin biosynthetic pathway and Y. lipolytica was enhanced by enzyme fusion and integration site engineering. Then, the production of cordycepin was improved by the enhancement of adenosine supply. Furthermore, through modular engineering, the production of cordycepin was achieved at 3588.59 mg/L from glucose. Finally, 3249.58 mg/L cordycepin with a yield of 76.46 mg/g total sugar was produced by the engineered strain from the mixtures of glucose and molasses. This research is the first report on the de novo high-level production of cordycepin in the engineered Y. lipolytica.

[Advances in the biosynthesis of pentostatin].

Pentostatin is a nucleoside antibiotics with a strong inhibitory effect on adenosine deaminase, and is widely used in the clinical treatment of malignant tumors. However, the high cost hampers its application. In the past 10 years, the biosynthesis of pentostatin were focused on strain breeding, optimization of medium composition and fermentation process. To date, there are no reviews summarizing the elucidated biosynthetic mechanism of pentostatin. This review starts by introducing the various chemical route for production of pentostatin, followed by summarizing the mechanisms of pentostatin biosynthesis in different microorganisms. Finally, challenges for biosynthesis of pentostatin were discussed, and strategies for regulating and improving the microbial synthesis of pentostatin were proposed.