Targeting stress-response genes for control of Aspergillus using antifungal natural compounds.

Jong H. Kim1, Bruce C. Campbell1, Jiujiang Yu2, Deepak Bhatnagar2, and Thomas E. Cleveland2.

Author address: 

1Plant Mycotoxin Research Unit, Western Regional Research Center, USDA-ARS, 800 Buchanan St., Albany, California 94710 USA; 2 Food and Feed Safety Unit, Southern Regional Research Center, 1100 Robert E. Lee Blvd, New Orleans, Louisiana, 70124 USA

Abstract: 

Signal transduction and stress-response genes of fungal pathogens play important roles in pathogenesis. Many genes in Saccharomyces cerevisiaeare interrelated to genes of many fungal pathogens. To discover stress-response genes critical for virulence, an in silico database of transduction/stress-response pathway genes of Aspergillus flavus was constructed based on orthologs of S. cerevisiae. Succesful functional complementation of an antioxidative stress gene from A. flavus, mitochondrial superoxide dismutase (sodA), in a sod2delta yeast mutant verified that S. cerevisiae could serve as a model system for functional genomics of A. flavus. Phenolics are released by plants during fungal infection and their detoxification is necessary for fungal pathogenesis. We developed a high throughput yeast bioassay to screen phenolics for potential antifungal or antiaflatoxigenic activities. Yeast genes affected by active compounds were identified, including a number of signal transduction and antioxidative stress response genes important to fungal tolerance. Then, compounds were used against A. flavus. A 100-fold synergism of strobilurin fungicides was achieved by targeting certain genes with phenolics.
2005

abstract No: 

374

Full conference title: 

23rd Fungal Genetics Conference
    • Fungal Genetics Conference 23rd (2002)