Fungal Enzyme Modification Controls Purine Metabolism in Verticillium Wilt

Verticillium wilt, a destructive plant disease caused by the fungus Verticillium dahliae, inflicts severe agricultural losses worldwide. While the interaction between this pathogen and its host plants has been studied extensively, how metabolic regulation shapes fungal development and disease-causing ability has remained poorly understood. A new study addresses this gap by examining S-acylation, a post-translational modification in which fatty acids are attached to proteins to alter their properties and functions, a process that had not previously been characterized in V. dahliae.

Through systematic analysis, the researchers found that the protein S-acyltransferase VdERF2 is essential for both the development and the pathogenicity of V. dahliae. Comparative S-acyl-proteomic analyses then showed that VdERF2-dependent S-acylation is significantly enriched in metabolic pathways, with purine metabolism standing out among the affected processes. This pointed to a specific biochemical route through which the modification could influence the fungus’s behavior during infection.

Among the identified substrates was VdHIUH, an enzyme that converts uric acid to allantoin in purine metabolism. The study demonstrated that VdHIUH requires S-acylation for its full function in fungal development and virulence. VdERF2-mediated S-acylation enhances the activity of VdHIUH, thereby reducing the accumulation of uric acid inside the fungus. When this modification is defective, uric acid builds up, linking the chemical modification directly to a metabolic bottleneck.

The researchers also traced the downstream consequences of this defect. Allantoin, the product of VdHIUH activity, was found to reduce the reactive oxygen species that become elevated when VdHIUH lacks its S-acylation, partially alleviating the fungal developmental impairment caused by the defect. This chain of effects, from protein modification to enzyme activity to metabolite levels to oxidative stress, outlines a mechanism by which S-acylation modulates purine metabolism in V. dahliae. The authors suggest that these findings offer new insight into the molecular basis of fungal pathogenicity and highlight potential targets for improving crop resistance to Verticillium wilt.

Subject of Research: S-acylation-dependent regulation of purine metabolism in the Verticillium dahliae fungus

Article Title: Comparative S-acyl-proteomics reveals post-translational modulation of fungal purine metabolism for Verticillium wilt

Article References: Li, C., Zhang, W., Cui, S., Zhang, J., Li, Y., Liu, X., Li, Y., Wang, Z., Huang, W., Li, G., Yang, C., Yan, S., & Lai, J. (2026). Comparative S-acyl-proteomics reveals post-translational modulation of fungal purine metabolism for Verticillium wilt. PLOS Pathogens, 22(10), e1014730. https://doi.org/10.1371/journal.ppat.1014730

Image Credits: AI Generated

DOI: 10.1371/journal.ppat.1014730

Keywords: Verticillium dahliae, Verticillium wilt, S-acylation, post-translational modification, purine metabolism, VdERF2, VdHIUH, allantoin, uric acid, reactive oxygen species, fungal pathogenicity, crop resistance