Metabolic Engineering Through Manipulation of Cofactors: Effects on Production of Succinate

William Marsh Rice University, Houston TX

Investigators

Abstract

The objective of this project is to systematically investigate the cellular responses of Escherichia coli in regulating its metabolic activities upon precise genetic perturbations. The synthesis of succinic acid will be used as a model system. The role of two key cofactors, NADH/NAD+ and CoA, will be investigated. In addition, the effect of enzyme properties on the redistribution of metabolic fluxes and on succinic acid productivity will also be investigated. The specific objectives are to test the following hypotheses to increase flux through the succinic acid synthesis pathway: (1) reducing the effect of feedback inhibition of an enzyme which is involved in a key step of the product synthesis pathway; (2) if the product synthesis pathway requires the cofactor NADH, the overall flux through that particular pathway will be enhanced by manipulating the NADH/NAD+ pool; and (3) in situations where a cofactor has multiple roles, fine tuning of the co-factor level may be required for optimal product formation.