Monday, July 25, 2011
Grand Ballroom, 5th fl (Sheraton New Orleans)
With the increase in price of traditional fuels, alternative renewable energy sources are needed, and the production of biofuels has become imperative. So far, studies of E. coli have been focused on using glucose as feedstock for the production of ethanol, a biofuel. In contrast, glycerol has only recently become abundant, and hence its utilizations has not been studied in detail using mathematical modeling. This work focuses in the implementation of a kinetic model to study the metabolism of glycerol in Escherichia coli.
Kinetic models are useful to identify the control structure within a specific pathway. The kinetic model developed in this work accounts for the transport and dissimilation of glycerol, glycolysis and ethanol synthesis. Using this model, we were able to elucidate the control structure of the pathways involved on glycerol utilization and ethanol synthesis. Glycerol dehydrogenase and dihydroxyacetone kinase were identified as the enzymatic steps controlling the glycolytic flux during the fermentative metabolism of glycerol in E. coli. The control structure predicted by the MCA was experimentally verified and the findings used to identify genetic targets that led to an improvement in the anaerobic production of ethanol from glycerol.