Project Number: 5010-42000-044-00-D
Project Type: In-House Appropriated
Start Date: Jan 19, 2011
End Date: Jan 18, 2016
The overall goal of this project is to develop strategies that reduce contamination of maize with mycotoxins produced by Fusarium and thereby improve the safety of maize for human and animal consumption. To achieve this goal, we propose research that addresses the four objectives listed below. Objective 1: Identify and characterize Fusarium genes and proteins that regulate production of fumonisin mycotoxins and other secondary metabolites; Objective 2: Identify critical components of fungal-plant-environmental interactions that affect fumonisin contamination in maize; Objective 3: Identify variation in distribution and arrangement of biosynthetic genes for mycotoxins and other secondary metabolites among Fusarium species; Objective 4: Develop new ambient ionization mass spectrometry (MS) techniques for the convenient analysis of mycotoxins from a variety of food related matrices.
Fumonisin mycotoxins are common maize contaminants that pose risks to food safety and public health, as well as livestock health. The risks result from the ability of fumonisins to cause diseases, including cancer and neural tube defects. Fumonisin contamination is a direct result of infection of maize (corn) by the fungus Fusarium verticillioides, which is a major cause worldwide of maize ear rot but is also present at a high frequency in healthy maize kernels. Fumonisin levels are, however, generally much higher in rotted kernels than in healthy infected kernels. Understanding the genetic regulation of fumonisin production and the pathogenesis of F. verticillioides in maize is critical for the development of strategies to prevent fumonisin contamination. We propose to use molecular genetics and functional genomics to identify and characterize F. verticillioides genes that regulate fumonisin biosynthesis or affect pathogenesis, because such genes are potential targets for strategies to prevent fumonisin contamination. We also propose to examine genes responsible for production of two less well understood Fusarium mycotoxins, fusarins and fusaric acid, as part of efforts to clarify the importance of the toxins in food safety. Essential for efforts to improve food safety are methods to reliably detect and quantify contaminants. Thus, we also propose to develop ambient mass spectrometry (MS) for fumonisin analysis directly from maize. This method will be an improvement over exiting methods because it will bypass sample preparations and chromatography that are required for current MS analyses. Together, the results of our research will elucidate genetic factors that control mycotoxin production in Fusarium, improve methods for mycotoxin analysis, and contribute to strategies that reduce fumonisin contamination of maize. The results have the potential to improve the safety of maize for consumption by humans, and will provide tools to seed and biotechnology companies, regulatory agencies, and other research scientist working to reduce mycotoxin contamination.