Open AccessBiosynthetic Origin of Aflatoxin G1: Confirmation of Sterigmatocystin and Lack of Confirmation of Aflatoxin B1 As Precursors
Author(s) -
A. Henderberg,
Joan W. Bennett,
L. S. Lee
Publication year - 1988
Publication title -
microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.019
H-Index - 179
eISSN - 1465-2080
pISSN - 1350-0872
DOI - 10.1099/00221287-134-3-661
Subject(s) - sterigmatocystin , aflatoxin , aspergillus parasiticus , aspergillus flavus , chemistry , mycotoxin , mutant , aspergillus , biology , chromatography , food science , biochemistry , microbiology and biotechnology , gene
The origin of aflatoxin G1 was studied using mutant strains of Aspergillus parasiticus blocked early in the pathway and by tracing 14C-labelled aflatoxin B1 (AFB1) in wild-type A. flavus and A. parasiticus strains. Sterigmatocystin (ST) was a precursor of AFB1, AFG1 and AFG2 in the four mutants examined. The identity of AFG1 was confirmed by mass spectrometry. No evidence for conversion of AFB1 to AFG1 was found. A rigorously controlled study of conversions of radioactivity based on preparative thin-layer chromatography of aflatoxins demonstrated that low levels of aflatoxin interconversions previously reported in the literature might actually be artifacts.