AFLATOXIN CONTROL THROUGH TARGETING MECHANISMS GOVERNING AFLATOXIN BIOSYNTHESIS IN CORN AND COTTONSEED
Location: Food and Feed Safety Research
Title: TRYPTOPHAN’S EFFECTS ON AFLATOXIN BIOSYNTHESIS AND ITS REGULATION IN ASPERGILLUS FLAVUS
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 21, 2006
Publication Date: April 8, 2006
Citation: Wilkinson, J.R., Yu, J., Bland, J.M., Scheffler, B.E., Kim, H.S., Nierman, W.C., Cleveland, T.E. 2006. Tryptophan’s effects on aflatoxin biosynthesis and its regulation in Aspergillus flavus. In: Proceedings of the 8th European Conference on Fungal Genetics, April 6-12, 2006, Vienna, Austria. p. 68.
Aflatoxins are secondary metabolites produced by the fungi Aspergillus flavus and A. parasiticus. These compounds are toxic and carcinogenic. Many nutritional and environmental factors are known to affect aflatoxin formation. In order to better understand the molecular mechanisms that control or regulate aflatoxin production changes in aflatoxin biosynthesis in A. flavus and A. parasticus grown in yeast extract, sucrose media supplemented with 50 mM tryptophan was examined. A. flavus grown in the presence of 50 mM tryptophan was found to have significantly reduced aflatoxin B1 and B2 biosynthesis, but A. parasitiucs cultures had significantly increased B1 and G1 biosynthesis. To determine if the effects of tryptophan were due to decreased levels of biosynthesis, microarray analysis of the effects of tryptophan on regulation of aflatoxin biosynthesis was performed. Preliminary analysis by MeV (TIGR) revealed 1174 genes occurred in both A. flavus and A. parasticus. Nine genes were found to be significant across the experiments by T-test. Further investigation of these candidate genes may identify potential regulators involved in aflatoxin biosynthesis.