Biosynthesis of citreoviridin. A carbon-13 n.m.r. study

Abstract

The complete assignment of the natural abundance ¹³C n.m.r. spectrum of citreoviridin, a mycotoxin produced by Penicillium pulvillorum CSIR 1406, allowed a study of its biosynthetic origin using ¹³C-labelled precursors. The results show that citreoviridin is derived from a C₁₈-polyketide formed from an acetate chain-starter unit and eight malonate units. The five remaining carbon atoms, i.e. the five methyl groups, are derived from (2S)-methionine.