Enhanced Production of Advanced Biofuels through Model Guided Synthetic Biology

Clemson University, Clemson SC

Investigators

Abstract

Principal Investigator: Mark Blenner Number: 1437836 This project seeks to improve the production of biodiesel in a genetically engineered strain of bacteria by understanding how sugars are converted into biodiesel. This will be accomplished through cell-based monitoring of the microorganism?s metabolism control processes through the principles of synthetic biology, which look holistically at how all metabolic processes within a cell interact with one another. A second aim of this project is control these metabolic processes to maintain high biodiesel production rates under changing environmental or process conditions. The results of this project may also apply to other metabolic pathways that produce sustainable fuels and chemicals, allowing transfer of these techniques from the laboratory to industry with more certainty and fewer complications. The project activities will also include efforts to engage women potentially interested in science, technology, engineering, and mathematics (STEM) careers in the state of South Carolina. Education and research will be integrated by providing training opportunities for students already in STEM, and local outreach to young women who might become more interested in STEM. Finally, this research will be integrated into a new elective course on protein and metabolic engineering offered at Clemson University. Technical Description This project will use simple unsteady-state kinetic models to rationalize protein engineering and synthetic biology based improvements to E. coli biodiesel production. Preliminary modeling studies identify inefficiencies due to pathway imbalance, and suggest that better flux distributions can be achieved through genetic and protein engineering efforts. Enzymes with catalytic efficiencies predicted to improve biodiesel production will be used. Critical enzymes will be engineered using directed evolution to relieve pathway bottlenecks. Protein-level feedback control will be engineered and combined with genetic level feedback control to allow pathway fluxes to remain high in spite of short and long time-scale metabolic perturbations. The combination of genetic and protein-level dynamic control will allow biofuel and other chemical producing systems to withstand perturbations from environmental variation and scale-up conditions without suffering large losses in yield and efficiency. The results of this project may lead to more general methods for balancing pathways that does not rely on explicit kinetic or flux data. The project activities will also include efforts to engage women potentially interested in science, technology, engineering, and mathematics (STEM) careers in the state of South Carolina. Education and research will be integrated by providing training opportunities for students already in STEM, and local outreach to young women who might become more interested in STEM. Finally, this research will be integrated into a new elective course on protein and metabolic engineering offered at Clemson University.