The antifungal activity of Lactiplantibacillus plantarum P9 relates to fatty acid synthesis and purine metabolism-related genes

Lactiplantibacillus (L.) plantarum has good inhibitory activity against Aspergillus (A.) flavus, but the understanding of the fungal inhibitory mechanism is still limited. Here, we used transcriptomics analysis to investigate changes in L. plantarum P9 gene expression in co-culture with A. flavus. The differentially expressed genes were analyzed using Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes. A gene cluster regulating fatty acid synthesis and metabolism, purine metabolism was discovered. Our results indicated that accelerated fatty acid synthesis and enhanced purine metabolism were likely the key factors for L. plantarum P9 to antagonize A. flavus. Co-culture treatment up-regulated the expression of the fatty acid synthesis-related genes families of acc and fab, and the purine metabolism-promoting gene families, guaC and pur. These genes helped improve cell membrane fluidity and promote cellular synthesis of DNA and RNA, which were possibly related to the antagonizing ability of L. plantarum P9 against A. flavus.