Membrane disruption and DNA binding of Fusarium graminearum cell induced by C16-Fengycin A produced by Bacillus amyloliquefaciens

Fusarium graminearum causes Fusarium head blight in wheat, barley, oats and stem rot of corn, and produces mycotoxins. C16-Fengycin A is a natural product produced by Bacillus amyloliquefaciens. In this work, the antifungal activity and mechanism of C16-Fengycin A against F. graminearum were investigated. The minimum inhibitory concentration (MIC) of C16-Fengycin A against F. graminearum was 64 mu g/mL, and the growth inhibitory assay also demonstrated that C16-Fengycin A exhibited a potent antifungal activity against F. graminearum. Membrane permeability, flow cytometric analysis and transmission electron microscope demonstrated that C16-Fengycin A disrupted the membrane integrity of F. graminearum. Meanwhile, C16-Fengycin A could lower the content of ergosterol, affecting the membrane structure and stability. Moreover, a gel retardation assay, spectroscopic approaches and simulative docking were used to assess the interaction of C16-Fengycin A and genomic DNA. Overall, the results revealed potential for development of C16-Fengycin A as the basis for novel agricultural food preservatives with fungicidal activity owing to its ability to damage cellular membranes and bind to DNA.