Product identification of polyketide synthase coded by Aspergillus nidulans wA gene

Abstract

The WA gene cloned from A. nidulans which was assumed to code for polyketide synthase involved in conidial spore pigment biosynthesis was expressed in a heterologous host fungus A. oryzae using starch inducible fungal expression plasmid pTAex3. The A. oryzae transformant produced starch inducible compounds, whose structures were identified to be citreoisocoumairn and its derivatives. Apparent heptaketide nature of these compounds identified that the wA gene codes for a heptaketide synthase of A. nidulans.