Surface modified sulfur nanoparticles can escape the glutathione reductase mediated detoxification system in fungi

The antifungal effects of orthorhombic (~10 nm; spherical) and monoclinic (~50 nm; tetrapod) sulfur nanoparticles (SNPs) were studied against the NADPH-dependent glutathione reductase (GR) mediated xenobiotic detoxification system (GSH-GSSG) in filamentous fungi (Aspergillus niger as a model organism). Both the SNPs induced significant reduction in fungal growth and spore formation, and also introduced marked deformities on the surface of conidiophores at their sub-inhibitory concentrations. A genome wide transcriptome profile then revealed manifold reduction in the expression of GSH-GSSG transcripts among SNPs treated fungal isolates, which is unusual for the micron sized elemental sulfur but probably effective in terms of antifungal efficacy.