Abstract

In recent years there has been increased interest in the production of valuable materials through the use of microbes to convert biomass1. The filamentous fungus Aspergillus terreus is already of industrial value through its ability to produce the cholesterol lowering drug lovastatin, and the bulk commodity chemical itaconic acid 2. While itaconic acid already has a market of up to 80,000 tons per year, it can also be used as a replacement for the petrochemical derived acrylic acid, which has a market of 2,100,000 tons, for several applications3. However, additional research is needed to improve production of itaconic acid using A. terreus to lower its production cost to make it more competitive against acrylic acid. Unfortunately, research into itaconic acid production has been hampered by shortcomings in genetic manipulations of A. terreus3. Here, is described the first use of CRISPR-Cas9-based genetic modifications as a means of producing new strains of A. terreus for future study. This study describes the creation of stable strains with genetic changes, opening the door for future investigations into A. terreus that may improve itaconic acid production.