AFLATOXIN CONTROL THROUGH TARGETING MECHANISMS GOVERNING AFLATOXIN BIOSYNTHESIS IN CORN AND COTTONSEED
Location: Food and Feed Safety Research
Title: Potential of Aspergillus flavus Genomics for Applications in Biotechnology
Submitted to: Trends in Biotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 19, 2008
Publication Date: December 19, 2008
Citation: Cleveland, T.E., Yu, J., Fedorova, N., Bhatnagar, D., Payne, G.A., Nierman, W.C., Bennett, J.W. 2009. Potential of Aspergillus flavus Genomics for Applications in Biotechnology. Trends in Biotechnology. 27(3):151-157.
Interpretive Summary: Aspergillus flavus is a common soil inhabitant and a weak plant pathogen that infects a broad range of important agricultural crops. A. flavus produces aflatoxins, the most potent naturally occurring toxic compounds. Consumption of aflatoxin-contaminated foods and feeds causes acute toxicity and long term carcinogenicity. The aim of sequencing and analysis of the A. flavus genome is to understand the mechanism of aflatoxin formation and define strategies to reduce aflatoxin contamination of food and feed commodities. In addition, it also help us to identify genes involved in degrading organic materials for biofuel production, as well as novel compounds that potentially have pharmaceutical use. The possible strategy to reduce aflatoxin and potential benefit of A. flavus genomics have been reviewed and discussed.
Aspergillus flavus is a common saprophyte and opportunistic pathogen that survives in the natural environment by extracting nutrition from plant debris, insect carcasses and a variety of other carbon sources. A. flavus produces numerous secondary metabolites and hydrolytic enzymes. The primary objectives of the A. flavus genomics program are to reduce and eliminate aflatoxin contamination in food and feed; to discover genetic factors that contribute to plant and animal pathogenicity; to identify new secondary metabolism gene clusters with potential use in the pharmaceutical industry; and to enlarge our knowledge of the enzymes involved in biomass degradation. For this purpose, A. flavus Expressed Sequence Tags (EST) and whole genome sequencing have been completed. Three different types of A. flavus microarrays have been constructed and used in gene profiling and functional genomics studies. Analysis of the A. flavus genome reveals numerous genes and gene clusters that are potentially involved in the formation of aflatoxin and other secondary metabolites as well as in the degradation of complex carbohydrate polymers. Bioinformatics analysis of these putative secondary metabolism pathways may facilitate the discovery of new compounds, including metabolites with pharmaceutical properties, as well as new enzymes for biomass degradation. Experimental characterization and functional analysis remain the rate limiting steps in translating genomics data into the drug discovery pipeline as well as for harnessing other aspects of Aspergillus metabolism.