Author
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Hua, Sui Sheng |
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Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 5/20/2014 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: The yeast, Pichia anomala strain WRL-076, was successfully discovered as an effective antagonist against Aspergillus flavus through a visual bioassay. The bioassay was designed by simultaneously scoring for growth inhibition and aflatoxin reduction. A nor mutant of A. flavus was used as an indicator strain because it produced a red orange color when aflatoxin biosynthesis is turned on. White color of nor mutant means the yeast strain inhibited aflatoxin production The transcriptional response of P. anomala grown in medium inoculated with A. flavus was investigated by determining expression rate of the Exo-'-1, 3-glucanase genes, PaEXG1 and PaEXG2 relative to control yeast cells. PaEXG1 and PaEXG2 were increased by 4 and 5 fold respectively. The major volatile compound produced by P. anomala WRL-076 is 2-phenylethanol (2-PE). It inhibited spore germination and aflatoxin (AF) production of A. flavus. The inhibition was correlated with significant down regulation of clustering AF biosynthesis genes as evidenced by several to greater than 10,000-fold decrease in gene expression. We found that 2-PE also altered the expression patterns of chromatin modifying genes, MYST1, MYST2, MYST3, gcn5, hdaA and rpdA. |
