Direct starch to fermentable sugar as feedstock for the production of isoprene, isoprenoid precursor molecules, and/or isoprenoids

A method for the production of isoprenoids by recombinant microbial host cells in culture, wherein the host cells comprise one or more heterologous nucleic acids encoding one or more mevalonate (MVA) pathway polypeptides and one or more polyprenyl pyrophosphate synthase polypeptides, the method comprising:

• a. inactivating endogenous enzyme activity in a whole or fractionated grain, wherein the endogenous enzyme activity is capable of producing kojibiose or nigerose, wherein said inactivation comprises temporarily lowering the pH of an aqueous slurry of the whole or fractionated grain to about pH 1 to 4;
• b. treating the whole or fractionated grain of step (a) with a starch solubilizing alpha amylase and a glucoamylase, wherein the treatment is at a temperature below the gelatinization temperature of the starch in the grain, wherein the pH is adjusted to about pH 4.0 to 6.5, wherein the concentration of the alpha amylase is between about 5 to 25 AAU/gds, and wherein the treatment produces a fermentable sugar feedstock, wherein the fermentable sugar feedstock comprises a reduced concentration of DP-2 saccharides in comparison to fermentable sugar feedstocks that are not made by the inactivation of step (a) and the treatment of step (b), wherein said reduced concentration of DP-2 saccharides comprises reduced concentration of kojibiose or nigerose;
• c. culturing the recombinant host cells in culture media comprising the fermentable sugar feedstock;
• and
• d. producing isoprenoids.

A method for the production of mevalonate by recombinant microbial host cells in culture, wherein the host cells comprise one or more heterologous nucleic acids encoding one or more mevalonate (MVA) pathway polypeptides, the method comprising:

• a. inactivating endogenous enzyme activity in a whole or fractionated grain, wherein the endogenous enzyme activity is capable of producing kojibiose or nigerose, wherein said inactivation comprises temporarily lowering the pH of an aqueous slurry of the whole or fractionated grain to about pH 1 to 4;
• b. treating the whole or fractionated grain of step (a) with a starch solubilizing alpha amylase and a glucoamylase, wherein the treatment is at a temperature below the gelatinization temperature of the starch in the grain, wherein the pH is adjusted to about pH 4.0 to 6.5, wherein the concentration of the alpha amylase is between about 5 to 25 AAU/gds, and wherein the treatment produces a fermentable sugar feedstock, wherein the fermentable sugar feedstock comprises a reduced concentration of DP-2 saccharides in comparison to fermentable sugar feedstocks that are not made by the inactivation of step (a) and the treatment of step (b), wherein said reduced concentration of DP-2 saccharides comprises reduced concentration of kojibiose or nigerose;
• c. culturing the recombinant host cells in culture media comprising the fermentable sugar feedstock;
• and
• d. producing mevalonate.