Popis: |
The present invention relates to modified eukaryotic microbial cells that have been engineered for producing fermentation products such as fatty acids, 1-alcohols, [beta]- keto-acids and -alcohols, [beta]-hydroxyacids, 1,3-diols, trans-[Delta]2-fatty acids, alkenes, alkanes and derivatives thereof, 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 [beta]-oxidation cycle in the cytosol of the cell 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 oxic conditions, acetyl-CoA from the non- fatty acid carbon source to feed into and drive the [beta]-oxidation cycle in the bio synthetic direction and, to express termination enzymes for conversion of reaction [beta]-oxidation cycle intermediates into the desired fermentation product. The invention further relates to oxic processes wherein the cells are used to produce fermentation products such as fatty acids, 1-alcohols, [beta]-keto-acids and -alcohols, [beta]- hydroxyacids, 1,3-diols, trans-[Delta]2-fatty acids, alkenes, alkanes or derivatives thereof. |