The present invention provides for the manipulation of cofactor usage in a recombinant host cell to increase the formation of desirable products. In some embodiments, the invention provides for a recombinant microorganism comprising a mutation in one or more native enzymes such that their cofactor specificity is altered in such a way that overall cofactor usage in the cell is balanced for a specified pathway and there is an increase in a specific product formation within the cell. In some embodiments, endogenous enzymes are replaced by enzymes with an alternate cofactor specificity from a different species.
STATEMENT REGARDING FEDERALLY-SPONSORED RESEARCH AND DEVELOPMENT
 This invention was funded, in part, by the United States government under a Department of Energy Biomass Program award #DE-FC36-07G017057. This invention was also funded, in part, by the BioEnergy Science Center (BESC) under the DOE Office of Science through award number DE-POS2-06ER64304. The U.S. Government has certain rights in this invention.