New Promoters to Improve Heterologous Protein Production in Penicillium chrysogenum

Filamentous fungi such as Aspergillus and Penicillium are used as hosts for expression and secretion of heterologous proteins and secondary metabolites. Studies have shown the promiscuous nature of fungi in recognizing transcriptional and translational elements present in genes from other fungal species. However, only few promoters have been characterized so far in Penicillium chrysogenum. To address this need, a set of heterologous and homologous promoters were tested in a reporter system.. We combined available synthetic biology tools such as BioBricks and in vivo homologous recombination in Saccharomyces cerevisiae in order to engineer twelve Penicillium and Aspergillus promoter pathways driving the expression of GFP while constitutive expression of DsRed was used as an internal strandard. These pathways were tested using the BioLector technology in fermentations with a P. chrysogenum strain and classified in strength and expression profile. This catalog of promoters will be used in future synthetic biology projects to tune the expression of target genes.