Researchers at the Institute of Botany, Chinese Academy of Sciences found molecular pathways and regulatory mechanisms for the biosynthesis of fungal patulin
Dissection of patulin biosynthesis, spatial control and regulation mechanism in Penicillium expansum
Patulin, a secondary metabolite of polyketones produced by fungi, is an important mycotoxin that causes pollution of fruits and their processed products. It is toxic to humans and animals and brings great health to consumers. Threat. Therefore, the molecular basis of patulin biosynthesis in fungi is analyzed, and its synthetic pathway and regulation mechanism are clarified, which is essential for the prevention and control of postharvest patulin.
The Tian Shiping Research Group of the Institute of Botany, Chinese Academy of Sciences has long been engaged in post-harvest pathology research. In the early stage, the research team identified a patulin synthetic gene cluster containing 15 genes from Penicillium expansum, which proved the regulation of the gene in the cluster on the synthesis of patulin, revealing the patulin. The molecular basis of biosynthesis and the discovery of a transcription factor PePacC that responds to environmental pH signals can control patulin synthesis by regulating gene expression in this gene cluster. Recently, on the basis of the research, the research team used gene knockout, mutant substrate feeding, protein heterologous expression and in vitro catalysis to clarify the catalytic enzyme and its coding of the 8-step reaction in the patulin biosynthesis pathway. gene. Based on molecular genetics and biochemical evidence, the researchers determined that the product of the fourth step of the patulin biosynthesis pathway is gentisaldehyde instead of m-hydroxybenzaldehyde, which has long been based on this reaction. Controversy over the formation of chemical products. At the same time, the researchers also identified the catalytic enzymes, transporters and regulatory proteins in the synthetic pathway by subcellular localization of all 15 proteins and related regulatory factors PeLaeA, PeVeA and PeVelB encoded by the patulin synthesis gene cluster. The subcellular distribution outlines the molecular network of patulin in the intracellular biosynthesis and transport pathway of Penicillium.
This study not only provides molecular evidence for further understanding of the molecular basis, transport pathways and regulatory networks of patulin biosynthesis in fungi, but also provides new ideas for the development of precise and efficient control techniques. The research results are of great significance for realizing the control of patulin contamination from the source and ensuring the quality and safety of the fruit and its processed products.
The study was officially published on March 13th in the International Academic Journal of Environmental microbiology. Researcher Li Boqiang from the research team of Tian Shiping, as well as doctoral student Chen Yong, graduated doctoral student Zong Yuanyuan as the co-first author of the paper, and researcher Tian Shiping as the author of the paper. Professor Long Manyuan from the University of Chicago gave guidance on research work. The research was funded by the National Key Research and Development Program, the National Natural Science Foundation, and the Chinese Academy of Sciences Youth Innovation Promotion Association.
