The Department of Defense (DoD) relies on the manufacture of large volumes of explosives and propellants, which collectively produce tens of millions of pounds of hazardous chemical waste each year. This waste poses environmental and health risks, which are compounded by failures in containment or compliance, and its disposal incurs significant cost. As such, there have been concerted efforts over past decades to develop new synthetic approaches to reduce the reliance on solvents and strong acids in energetics production. In particular, one promising alternative synthesis approach is biological based production, in which non-toxic enzymes and microbes perform chemical conversions instead of solvents and acids. Such approaches can reduce hazardous waste quantities by orders of magnitude. Despite this potential, efficient, scalable methods for bio-production of energetics have not yet been realized. The objective of this project is to develop transferable bio-production systems that address several different processes critical to the production of energetic materials, and to validate the viability of these systems for scalable production. These include green routes to known and novel precursors to energetic materials, and new pathways for nitration.

Our Foundry has developed a suite of platform technologies that facilitate genetic design. These capabilities include bioinformatic genome mining, high-throughput enzyme characterization, retro-biosynthesis, strain optimization, and in partnership with Advanced Biofuels and bioproducts Process Development Unit, pilot-scale production. The project team will apply these tools to design, prototype, refine, and scale novel biosynthetic pathways for microbial production of specific precursors. The deliverables of the research will include engineered microbial strains for chemical production, testable quantities of chemicals for at least two different targets, scalability and cost data obtained via pilot-scale production, and detailed characterization data for dozens of new enzymes for use in guiding future designs of biosynthetic pathways.

These efforts will yield sustainable alternative means to address three different energetics production processes identified by SERDP that will dramatically reduce hazardous waste streams, both in volume and in content. In addition, for at least two of these targets, the research team will have developed pilot scale production processes and associated quantitative performance data that can be directly transferred to manufacturing. Finally, this work will also produce considerable empirical data to define the overall potential in combining different enzymes to access diverse nitration products, which will also have relevance for biodesign beyond energetics (e.g. for therapeutics).