Transcriptomic Analysis of Colletotrichum Reveals Metabolic Responses During Interaction with Burkholderia vietnamiensis FBCC-B8049

Burkholderia vietnamiensis FBCC-B8049, isolated from a freshwater environment, has been confirmed to exhibit antifungal activity as well as plant growth-promoting effects. In particular, FBCC-B8049 showed antifungal activity against plant pathogenic fungi such as the genus Colletotrichum, which cause diseases in crops such as apple, mango, and pepper. In this study, transcriptome analysis was performed to investigate the physiological and defense responses of C. acutatum during in vitro dual culture. To analyze the antifungal interaction at the transcriptional level, dual-culture between the fungus and bacterium was conducted on solid media. RNA-seq analysis was performed to identify differentially expressed genes (DEGs), followed by Gene Ontology (GO) analysis and KEGG pathway enrichment analysis. The results revealed differentially expressed genes under the conditions compared to the fungal sole culture. Heatmap analysis showed clear differences in gene expression patterns between the two conditions. KEGG pathway enrichment analysis indicated significant changes in multiple metabolic pathways, including oxidative phosphorylation, glycolysis/gluconeogenesis, starch and sucrose metabolism, and valine, leucine, and isoleucine degradation. These findings suggest that the interaction with the antifungal bacterium significantly affects energy metabolism and carbon metabolism in the fungal pathogen. This study provides insights into the defense mechanisms of plant pathogenic fungi in response to antifungal bacteria and contributes to understanding the molecular mechanisms and potential metabolic disruption of fungal pathogens underlying bacterial antifungal activity.