One of the great challenges facing current and future generations is how to meet growing energy demands in an environmentally sustainable manner. Renewable energy sources, including wind, geothermal, solar, hydroelectric, and biofuel energy systems, are rapidly being developed as sustainable alternatives to fossil fuels. Biofuels are particularly attractive to the U.S., given its vast agricultural resources. The first generation of biofuel systems was based on fermentation of sugars to produce ethanol, typically from food crops. Subsequent generations of biofuel systems, including those included in the CABS project, will build upon the experiences learned from those early research results and will have improved production efficiencies, reduced environmental impacts and decreased reliance on food crops. Thermodynamic models predict that the next generations of biofuel systems will yield three- to five-fold more recoverable energy products. To address the technological challenges necessary to develop enhanced biofuel systems, greater understanding of the non-equilibrium processes involved in solar energy conversion and the channeling of reduced carbon into biofuel products must be developed. The objective of the proposed Center for Advanced Biofuel Systems (CABS) was to increase the thermodynamic and kinetic efficiency of select plant- and algal-based fuel production systems using rational metabolic engineering approaches grounded in modern systems biology. The overall strategy was to increase the efficiency of solar energy conversion into oils and other specialty biofuel components by channeling metabolic flux toward products using advanced catalysts and sensible design:1) employing novel protein catalysts that increase the thermodynamic and kinetic efficiencies of photosynthesis and oil biosynthesis
2) engineering metabolic networks to enhance acetyl-CoA production and its channeling towards lipid synthesis
and 3) engineering new metabolic networks for the production of hydrocarbons required to meet commercial fuel standards.