Abstract

Metabolic engineering aims to rewire cellular metabolism, typically of microorganisms, to produce fuels, chemicals, pharmaceuticals, and other valuable products from renewable resources. However, it is often challenging to achieve the titers, yields, and productivities required for commercial viability. Spatial and dynamical control of engineered metabolic pathways can greatly improve their efficiency to address this obstacle. We have developed strategies to enhance the flux and specificity of metabolic pathways by spatially compartmentalizing them in yeast mitochondria and synthetic organelles. This helps increase the local concentrations of enzymes and intermediate metabolites, prevent metabolic bottlenecks, and reduce metabolite loss to competing pathways. In addition, I will present a new strategy to dynamically control metabolic pathways using optogenetics. There are many advantages of using light to control metabolic pathways, including its orthogonality, tunability, and the ease with which it can be applied or removed instantly in any schedule to continuously manipulate metabolism throughout fermentations. I will present several optogenetic circuits we have built to control microbial growth and production with light, the impact they have on chemical production, and the strategies we have developed to overcome the limited light penetration of fermentations operating at high cell density in lab scale bioreactors. Finally, I will provide a perspective on how these technologies may come together to prescribe a new paradigm for spatial and dynamical control in metabolic engineering to improve microbial chemical production.