Planta Med 2012; 78 - PE9
DOI: 10.1055/s-0032-1320546

Characterization of the AN6448 cluster in Aspergillus nidulans

JB Nielsen 1, ML Klejnstrup 1, P Khorsand-Jamal 1, DK Holm 1, ML Nielsen 1, AM Kabat 2, C Rank 1, CH Gotfredsen 3, TO Larsen 1, UH Mortensen 1
  • 1Center for Microbial Biotechnology, Department of Systems Biology, Technical University of Denmark
  • 2Center for Systems Microbiology, Department of Systems Biology, Technical University of Denmark
  • 3Department of Organic Chemistry, Technical University of Denmark

With the aim of mapping the polyketome of A. nidulans we have made a library of strains, which individually overexpress PKS genes from an ectopic locus. A screen of this collection on different media demonstrated that AN6448 leads to production of 3-MOA. An inspection of the DNA sequence surrounding this gene uncovered a putative gene cluster including a gene, AN6446, with homology to transcription factors. Based on this observation, we decided to overexpress AN6446. A qRT-PCR analysis of this strain was used to delineate the borders of the gene cluster as well as to stimulate formation of cichorine and a number of new products, from the gene cluster. Subsequent deletion of all genes allowed several steps in the biosynthetic pathway in this cluster to be clarified.