Integrated Proteomic and Metabolomic Profiling of the Secretome of Fusarium verticillioides Reveals Candidate Associated Proteins and Secondary Metabolites

Fusarium verticillioides (F. verticillioides) is an important fungal pathogen known to infect a variety of economically critical crops, particularly maize, causing substantial yield reductions and economic losses worldwide. In addition to its direct damage to agricultural productivity, F. verticillioides threatens public health by producing/secreting potent compounds, including well-known fumonisins (FUMs), which pose significant health threats to both livestock and humans due to their toxicity and carcinogenicity. However, current knowledge of the materials secreted/produced by F. verticillioides, such as secreted proteins and additional secondary metabolites, remains limited. In the present study, we conducted an integrated secretome analysis of F. verticillioides at the exponential growth stage by using proteomic and metabolomic technologies. The results of the present study showed that proteomic analysis identified 185 proteins, including 138 fungus-specific proteins. GO enrichment of these 138 fungus-specific proteins yielded 24 significant terms spanning carbohydrate/polysaccharide and aminoglycan metabolic/catabolic processes, extracellular and membrane-anchored components, and hydrolase/peptidase activities. Meanwhile, KEGG analysis identified starch and sucrose metabolism as the sole significantly enriched pathway. Metabolomic analysis of medium supernatant showed that a total of 2352 metabolites were identified, with 110 unique to the medium supernatant of the fungal group, including fumonisins (A1, B2, B3, B4), fatty acids, and other bioactive compounds. KEGG pathway enrichment highlighted key metabolic pathways, including the TCA cycle, unsaturated fatty acid biosynthesis, and arachidonic acid metabolism. These findings provide new insights into the pathogenic mechanisms of F. verticillioides, suggesting candidates for virulence-associated functions and metabolic adaptations that potentially contribute to its pathogenicity.