, Volume 107, Issue 2–3, pp 121–126

A versiconal hemiacetal acetate converting enzyme in aflatoxin biosynthesis

  • D. P. H. Hsieh
  • C. C. Wan
  • J. A. Billington


Conversion of the aflatoxin biosynthetic intermediate versiconal hemiacetal acetate (VHA) in a cell free extract ofAspergillus parasiticus ATCC 15517 is investigated. The enzymatic reaction is monitored by a method using high performance liquid chromatography (HPLC). The major product of the enzymatic reaction is a water soluble compound not chloroform-extractable at pH 7.5. The product becomes chloroform extractable upon acidification of the reaction medium and is separated and quantitated by reversed-phase HPLC. It is tentatively identified as ‘versiconal hemiacetal alcohol,’ which is converted to versicolorin C (VC) upon acid treatment.

Key words

aflatoxin biosynthesis Aspergillus parasiticus versiconal hemiacetal acetate versicolorin C enzymology 


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Copyright information

© Kluwer Academic Publishers 1989

Authors and Affiliations

  • D. P. H. Hsieh
    • 1
  • C. C. Wan
    • 2
  • J. A. Billington
    • 1
  1. 1.Department of Environmental ToxicologyUniversity of CaliforniaDavisUSA
  2. 2.Texaco Inc.BeaconUSA

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