Reversal of NAD(P)H cofactor dependence by protein engineering

There is increasing interest in utilization of engineered microorganisms for the production of renewable chemicals and next-generation biofuels. However, imbalances between the cofactor consumption of the engineered production pathway and the reducing equivalents provided by the cell have been shown to limit yields. This imbalance can be overcome by adjusting the cofactor dependencies of the pathway enzymes to match the available cofactors in the cell. We show how cofactor preference can be reversed by structure-guided directed evolution of the target enzyme.