Fig. 4
Changes in gene expression of secondary metabolite gene clusters in P. chrysogenum. Differential gene expression in P. chrysogenum was examined by pairwise comparison of the production strain with either wild-type or velvet deletion strain. As significant examples the gene cluster relevant for penicillin and yanuthone synthesis are shown. a Expressional changes and b cluster organization of the penicillin biosynthesis gene cluster and adjacent genes. c Expressional changes and d cluster organization of the yanuthone biosynthesis gene cluster. Blue bars represent the expressional change (log2-fold) comparing the industrial P2niaD18 with the wild type NRRL 1951, while orange bars represent the expressional changes induced by the velvet gene deletion. Relevant biosynthetic genes are indicated in red