Anoxic biological production of fuels and of bulk chemicals from second generation feedstocks

Summary

The present invention relates to modified eukaryotic microbial cells that have been engineered for producing fermentation products such as fatty acids, 1-alcohols alkenes, alkanes and derivatives thereof under anoxic conditions from second generation feedstocks, including at least pentoses. To this end the eukaryotic microbial cells have been modified to express enzymes of the fatty acid β-oxidation cycle in the cytosol of the cell,under anoxic conditions,in the absence of fatty acids and in the presence of a carbon source containing pentoses. The cells are further modified to express enzymes for metabolizing pentose like xylose and arabinose, as well as to express a metabolic route for producing under anoxic conditions, acetyl-CoA from the non-fatty acid carbon source to feed into and drive the β-oxidation cycle in the biosynthetic direction and,to express termination enzymes for conversion of reaction β-oxidation cycle intermediates into the desired fermentation product. The invention further relates to anoxic processes wherein the cells are used to produce fermentation products such as fatty acids, 1-alcohols,alkenes, alkanes or derivatives thereof.