The invention provides methods for producing products comprising improved host cells genetically engineered to have uncoupled productive and catabolic pathways. In particular, the present invention provides host cells having a modification in nucleic acid encoding an endogenous enzymatic activity that phosphorylates D-glucose at its 6th carbon and/or a modification of nucleic acid encoding an enzymatic activity that phosphorylates D-gluconate at its 6th carbon. Such improved host cells are used for the production of products, such as, ascorbic acid intermediates. Methods for making and using the improved host cells are provided. Nucleic acid and amino acid sequences for glucokinase and gluconokinase are provided.