Abstract
Non-aflatoxin-producing isolates ofAspergillus flavus from nature and isolates ofA. flavus that had lost their toxigenic trait following laboratory transfer were compared biochemically. After the addition of aflatoxin B1 precursors sterigmatocystin or O-methylsterigmatocystin to whole cell cultures, the non-toxin producing isolates from nature remained non-toxigenic while toxigenicity was restored in the nontoxigenic laboratory strains. Results imply a lack of enzymes needed for biochemical conversions of precursors to aflatoxin B1 in natural non-producers and suppression of these enzymes in the nonproducing laboratory strains.
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Lee, L.S. Metabolic precursor regulation of aflatoxin formation in toxigenic and non-toxigenic strains ofAspergillus flavus . Mycopathologia 107, 127–130 (1989). https://doi.org/10.1007/BF00707549
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DOI: https://doi.org/10.1007/BF00707549