Abstract

Metabolic engineering efforts that harness living organisms to produce natural products and other useful chemicals face inherent difficulties because the maintenance of life processes often runs counter to our desire to maximize important production metrics. These challenges are particularly problematic for commodity chemical manufacturing where cost is critical. A cell-free approach, where biochemical pathways are built by mixing desired enzyme activities outside of cells, can obviate problems associated with cell-based methods. Yet supplanting cell-based methods of chemical production will require the creation of self-sustaining, continuously operating systems where input biomass is converted into desired products at high yields, productivities, and titters. We call the field of designing and implementing reliable and efficient enzyme systems that replace cellular metabolism, synthetic biochemistry.