Integrated omics analyses reveal natamycin disrupts oxidative phosphorylation pathways in Magnaporthe oryzae

Magnaporthe oryzae, the causative agent of rice blast, is a devastating fungal pathogen that threatens global rice production. While natamycin is a known antimicrobial compound of microbial origin, its efficacy and precise mode of action against M. oryzae have remained largely unexplored. In this study, treatment with various concentrations of natamycin potently inhibited mycelial growth by 16.43% to 100%, with an EC₅₀ value of 11.77 mg/L. Pathogenicity of M. oryzae was also markedly reduced, declining to 4.1% of the control level under both in vitro and greenhouse conditions. To elucidate the underlying mechanisms, we adopted a multi-omics approach, integrating transcriptomic and metabolomic data. This analysis revealed a coordinated disruption of key metabolic processes, including amino acid biosynthesis and, most critically, oxidative phosphorylation. Functional validation suggested the involvement of oxidative phosphorylation, as overexpression of two key genes in this pathway MGG_17901 and MGG_04969 conferred significant natamycin tolerance to the fungus. Consistent with this, the overexpression strains also exhibited enhanced pathogenicity, indicating that MGG_17901 and MGG_04969 are involved in the virulence of M. oryzae. Molecular docking further identified binding sites between natamycin and the proteins encoded by these genes, and sequence alignments across 96 M. oryzae strains confirmed that these sites are conserved. Collectively, our findings suggest that natamycin disrupts these pathways and underscore its potential as a sustainable, naturally derived biocontrol agent for the management of rice blast disease.