Reduced fermentation glycerol and acetate using yeast expressing rubisco from gallionella capsiferriformans
AssigneeDanisco US Inc.
InventorJoseph F. Tuminello
Life of this patent
Estimating the term…
Abstract
The present compositions and methods relate to modified yeast cells that heterologously express the RuBisCo enzyme from a particular species of iron-oxidizing bacteria. The modified yeast cells demonstrate reduced glycerol and acetate accumulation in fermentation, while maintaining high ethanol production, making them useful for large-scale ethanol production from starch substrates, where glycerol and acetate represent undesirable by-products.
Claims20
Modified yeast cells derived from parental yeast cells, the modified yeast cells comprising a genetic alteration that causes the modified cells to produce a ribulose-1,5-bisphosphate carboxylase-oxygenase (RuBisCo) enzyme from Gallionella capsiferriformans (GcRuBisCo).
Modified yeast cells derived from parental yeast cells, the modified cells comprising a genetic alteration that causes the modified cells to produce the ribulose-1,5-bisphosphate carboxylase-oxygenase (RuBisCo) enzyme from Gallionella capsiferriformans (GcRuBisCo), wherein the modified cells produce during fermentation a decreased amount of glycerol and/or acetate compared to the amount of glycerol and acetate produced by otherwise identical parental cells producing the RuBisCo enzyme from Thiobacillus dentrificans under identical fermentation conditions, and wherein the modified yeast cells and parental yeast cells both further comprise an exogenous gene encoding a phosphoribulokinase.
A method for decreasing the production of glycerol and acetate from yeast cells grown on a carbohydrate substrate, comprising:
- introducing into parental yeast cells a genetic alteration that causes the modified yeast cells to produce ribulose-1,5-bisphosphate carboxylase-oxygenase (RuBisCo) from Gallionella capsiferriformans.
The method of claim 20, wherein the fermentation product is ethanol.
Dependencies are inferred from the claim text.