Engineering for biofuels: exploiting innate microbial capacity or importing biosynthetic potential?

The ideal microorganism for biofuel production will possess high substrate utilization and processing capacities, fast and deregulated pathways for sugar transport, good tolerance to inhibitors and product, and high metabolic fluxes and will produce a single fermentation product. It is unclear whether such an organism will be engineered using a native, isolated strain or a recombinant, model organism as the starting point. The choice between engineering natural function and importing biosynthetic capacity is affected by current progress in metabolic engineering and synthetic biology. This Review highlights some of the factors influencing the above decision, in light of current advances.