Researcher wins grant to develop enzyme structures for bioenergy
Ian Wheeldon, assistant professor of chemical and environmental engineering at University of California, Riverside, has received a $360,000 grant from the Air Force Office of Scientific Research’s Young Investigator Program to create a more efficient biofuel cell using enzymes to convert sugars and carbohydrates into electricity. The funding will be allocated over three years.
Initial experiments demonstrated spatial organization of enzymatic pathways can increase power density in biofuel cells. There is currently, however, a lack of understanding regarding the fundamental principles that govern pathway kinetics.
“This limits engineering pathways to trial-and-error approaches,” Wheeldon said. “That’s an impossible task when increasingly complex pathways are considered, such as those need for advanced biofuel cells.”
To address this issue, Wheeldon plans to first study the relationship between multi-enzyme construction and reaction rate to discover the most efficient enzyme organization. He then will apply those principles into developing multi-enzyme pathways for enhanced anodes for enzymatic biofuel cells. By using an enzyme at both the anode (where electrical current flows into the device) and potentially on a cathode (where current flows out), the use of precious metals, such as platinum, for the catalysis is greatly reduced. Additionally, more potential energy can be released by breaking down sugar-based fuels multiple times using enzymatic pathways other than traditional fuel cells.
Although the research is aimed primarily at the development of biofuel cells for use in the medical field, the project does have implications for the biofuel industry.
“People are already looking at metabolic engineering and engineering organisms to produce biofuels and those pathways that produce the biofuels need some organization,” said Wheeldon. When trying to reassemble new enzymatic pathways for complex fuel production, such as biodiesel, Wheeldon said we need to spatially understand how to organize the pathways in terms of their ratio of one enzyme to the other, the distance between one enzyme to the next and the orientation of the enzymes. “We think the rules to do one will apply somewhat to the other,” Wheeldon continued.