The Evolution of the Satratoxin and Atranone Gene Clusters of .

is frequently isolated from damp building materials or improperly stored animal forage. Human and animal exposure to the secondary metabolites of this mold is linked to severe health effects. The mutually exclusive production of either satratoxins or atranones defines the chemotypes A and S. Based upon the genes (satratoxin cluster, SC1-3, or atranone cluster, AC1, ) that are supposed to be essential for satratoxin and atranone production, can furthermore be divided into three genotypes: the S-type possessing all - but no -genes, the A-type lacking the - but harboring all -genes, and the H-type having only certain and all genes. We analyzed the above-mentioned gene clusters and their flanking regions to shed light on the evolutionary relationship. Furthermore, we performed a deep re-sequencing and LC-MS/MS (Liquid chromatography-mass spectrometry) analysis. We propose a first model for the evolution of the genotypes. We assume that genotype H represents the most ancient form. A loss of the AC1 and the concomitant acquisition of the SC2 led to the emergence of the genotype S. According to our model, the genotype H also developed towards genotype A, a process that was accompanied by a loss of SC1 and SC3.