Zhejiang University Announces Technology Transfer of Echinocandin Analogs: A Synthetic Biology Platform for Next-Generation Antifungal Drug Development
Recently, the Institute of Industrial Technology Transfer of Zhejiang University released a public notice on the transformation of scientific and technological achievements, proposing to transfer“Echinocandin Compounds and Their Preparation Methods and Uses”Series of patent conversions, involving four invention patent applications in China, Japan, Europe, and the United States, with a listed transaction price ofRMB 1 million. The four patent application numbers are: Chinese Application CN202380044846.2, Japanese Application JP2024559395, European Application EP 23784285.1, and U.S. Application US18853119, which pertain to related technology transfer.
This achievement was completed by Zhejiang University.Xu Jinzhong, Yu Xionghui, Wang PinmeiThree researchers. According to the patent specification, the present invention belongs to the fields of synthetic biology and pharmacy, and relates to a class of echinocandin B deoxy analogs, as well as their preparation methods and uses.
The core patent series for this technology transfer (represented by Chinese Application No. CN202380044846.2) falls within the fields of synthetic biology and pharmaceutics. By employing genetic engineering techniques to construct specific biosynthetic gene clusters for expression in heterologous hosts, this approach enables the specific biosynthesis of deoxy analogs of echinocandin B. This technology overcomes the limitations of traditional chemical synthesis and fermentation using wild-type strains, allowing for the targeted preparation of echinocandin compounds with specific deoxygenation sites. These deoxy analogs maintain potent antifungal activity.
According to the patent specification, the current preparation methods for echinocandin B deoxy analogs are mainly divided intoChemical Synthesis Methods and Biosynthetic Methods, but all have significant flaws.
Chemical synthesis methods include:Chinese Patent CN1298410A discloses a method for converting mulundocandin into its C4-homotyrosine monodeoxy analog via Raney nickel-catalyzed hydrogenolysis under neutral conditions; U.S. Patent Application No. 222157 describes the reduction of pure echinocandin B to its monodeoxy analog using trifluoroacetic acid, NaCNBH₃, or NaBH(OAc)₃. The drawbacks of these chemical methods include the requirement for high-purity starting materials, low conversion efficiency, high costs, and the use of reagents that are harmful to human health.
As forExisting biosynthesis methods,It also faces the challenges of complex product profiles and difficult purification. According to the method disclosed in Chinese Patent Application CN101993477A, which involves mixing and reacting echinocandin B fermentation broth with an acidic solution to prepare deoxy analogs, this approach yields multiple echinocandin B deoxy analog components; however, it suffers from low conversion efficiency and high purification costs. Methods for preparing deoxy analogs by fermenting mutant strains with knocked-out oxygenase genes (such as ecdG or ecdH) have also been reported. However, the echinocandin B deoxy analog components obtained by this method are highly complex, with numerous by-products, low conversion efficiency, and high purification costs, making it unfavorable for industrial-scale production.
Therefore, there is an urgent need to identify a method with high conversion efficiency for the specific preparation of certain echinocandin B deoxy analogs, and to discover and prepare echinocandin B deoxy analogs with potent antifungal activity using this method.
According to the patent specification, the team of inventors designedBiosynthetic Gene Clusters of a Series of Echinocandin B Deoxy Analogs, by culturing and expressing it in a heterologous host, specifically generating the desired deoxy analog of echinocandin B. Compared with existing technologies, this method yields products with simpler composition, higher conversion efficiency, and fewer reaction impurities, facilitating separation and purification, which is conducive to industrialization.
This technology enables host cells to specifically synthesize target deoxy analogs by integrating a complete biosynthetic gene cluster (excluding specific hydroxylation modification genes) into a heterologous host. For example, by constructing a gene cluster lacking the ecdG and ecdH genes, echinocandin deoxy analogs with non-hydroxylated ornithine and homotyrosine residues (such as echinocandin E and echinocandin F) can be specifically produced.
This technology selectsAspergillus nidulansFungi such as *Aspergillus nidulans* serve as heterologous hosts. Compared with wild-type echinocandin B-producing strains, the fermentation broth of genetically engineered strains exhibits a simpler secondary metabolite profile and higher yield. The yield of deoxy analogs of echinocandin B produced by genetically transformed *Aspergillus nidulans* strains is significantly higher than that of echinocandin B produced by wild-type echinocandin B-producing strains.
The results indicate that the echinocandin compounds prepared according to the present invention exhibit potent antifungal activity and hold potential for development as antifungal agents. More importantly, a significant improvement in chemical stability was observed. Studies have shown that the structural instability of echinocandin B can result from the loss of hydroxyl groups on its ornithine and homo-tyrosine residues. However, in the deoxy analogs of echinocandin B of the present invention, particularly echinocandin E and echinocandin F, neither the homo-tyrosine nor the ornithine residues undergo hydroxylation modification. Nevertheless, compared with the cyclic hexapeptide structure of echinocandin B, these analogs demonstrate higher chemical stability, which is more favorable for subsequent chemical derivatization.
Echinocandins are a class of natural cyclic lipopeptide compounds discovered in the 1970s, whose chemical structure includesCyclic Hexapeptide Backbone and Fatty Acid Side Chain Structural Fragments(attached to the hexapeptide backbone via an amide bond). Echinocandins exhibit antifungal activity; their mechanism of action involves inhibiting β-(1,3)-D-glucan synthase in a non-competitive manner, thereby preventing fungal cell wall synthesis. A typical representative isEchinocandin B.
To date, new antifungal drugs have been developed through semi-synthesis based on echinocandin B, such asAnidulafungin and Rezafunginetc. These drugs are produced using the traditional technological route of “natural product fermentation plus chemical modification.”
Unlike traditional semi-synthetic approaches, the technology transferred by Zhejiang University employs synthetic biology strategies to achieve the specific preparation of deoxy analogs of echinocandins through customized design and heterologous expression of biosynthetic gene clusters. Compared with conventional methods, this approach offers advantages such as simpler product composition, higher conversion efficiency, and fewer reaction impurities. It represents a new technological direction and is expected to provide technical support for the development of novel antifungal drugs with independent intellectual property rights.
From the perspective of technological maturity, this achievement has completed the design of biosynthetic gene clusters, the construction of heterologous host expression systems, and preliminary evaluation of antifungal activity. According to the patent specification, this technology demonstrates significant advantages over traditional chemical synthesis and existing biosynthetic methods in terms of transformation efficiency, simplicity of product composition, and impurity control.