Recipients: Ross Thyer, James Chappell
A key manufacturing challenge of the 21st century is to find sustainable replacements for commodity chemicals and polymers that are currently derived from petrochemicals, a finite resource with a large carbon footprint. Current biomanufacturing efforts to produce these materials at scale generally rely on leveraging native metabolic pathways that yield valuable biomolecules (e.g. fermentation of alcohols by Acetogenic bacteria) or engineering non-native biosynthesis pathways in model microorganisms due to their genetic tractability (E. coli or S. cerevisiae). Unfortunately, many important biomolecules, such as commodity isoprenoids, are incompatible with these strategies because we lack microbes that naturally produce these compounds at high yields and cannot produce them cost-effectively in non-native producers. The Mycobacteriales are a group of metabolically diverse soil bacteria, many of which natively accumulate high levels of isoprenoid precursors and are capable of assimilating carbon from a wide range of ultra low-cost, sustainable feedstocks, such as simple alcohols and CO2. We propose Mycobacteriales can be leveraged as an isoprenoid production platform by introducing heterologous pathways from plants, the dominant source of valuable commodity isoprenoids. However, while synthetic biology methods to enable pathway construction and precise integration into the chromosome are well established in model microorganisms, the molecular tools for genome engineering do not exist for these species. In this proposal, the co-investigators will establish programmable CRISPR RNA-guided transposases (CAST systems) in environmental Mycobacteriales to enable integration of novel biosynthetic pathways and unlock their potential as hosts for sustainable biomanufacturing.
