De novo Synthesis of Alternariol in Conidia of Alternaria alternata

SUMMARY: Alternaria alternata synthesizes the polyketides alternariol (AOH) and alternariol monomethyl ether (AME) during the stationary growth phase when it is grown in the dark. In the present study it is reported that these polyketides are also found in the conidia of this fungus as well as the vegetative hyphae. Young conidia were able to synthesize AOH de novo as shown by the incorporation into AOH of [3H]acetate. Since AOH synthesis in the conidia showed no need for de novo synthesis of proteins, it is proposed that hyphal cytoplasm that is able to synthesize AOH is translocated into the developing conidia.