The present disclosure provides recombinant microorganisms and methods for the anaerobic production of 2,4-furandicarboxylic acid from one or more carbon sources. The microorganisms and methods provide redox-balanced and ATP positive pathways for co-producing 2,4-furandicarboxylic acid with ethanol and for co-producing 2,4-furandicarboxylic acid with ethanol and 1-propanol. The method provides recombinant microorganisms that express endogenous and/or exogenous nucleic acid molecules encoding polypeptides that catalyze the conversion of a carbon source into 2,4-furandicarboxylic acid and that coupled the 2,4-furandicarboxylic acid pathway with an additional metabolic pathway.

Disclosed are a recombinant acid-resistant yeast having lactic acid-producing ability and suppressed glycerol production and a method of preparing lactic acid using the same. More particularly, disclosed are a recombinant acid-resistant yeast into which a gene involved in lactic acid production is introduced and in which a gene involved in glycerol production is deleted or attenuated, and a method of preparing lactic acid using the same. When producing lactic acid using the recombinant acid-resistant yeast, the production of lactic acid is maintained while the production of glycerol is reduced, so crosslinking by glycerol can be suppressed in the oligomerization reaction for conversion to lactide, and thus the conversion yield of lactic acid to lactide can be increased.

The invention relates to a recombinant cell, preferably a yeast cell comprising: a) one or more heterologous genes encoding a glycerol dehydrogenase activity; b) one or more genes encoding a dihydroxyacetone kinase (E.C. 2.7.1.28 and/or E.C. 2.7.1.29); c) one or more heterologous genes encoding a ribulose-1,5-biphosphate carboxylase oxygenase (EC 4.1.1.39, RuBisCO); and d) one or more heterologous genes encoding a phosphoribulokinase (EC 2.7.1.19, PRK); and optionally e) one or more heterologous genes encoding for a glycerol transporter, wherein the recombinant yeast comprises overexpression of one or more PPP-genes. This cell can be used for the production of ethanol and advantageously produces little or no glycerol.

The present invention relates to a eukaryotic cell that is genetically modified comprising one or more heterologous gene encoding: a) D-glucose-6-phosphate dehydrogenase and/or b) 6-phosphogluconate dehydrogenase; and/or c) glucose dehydrogenase, gluconolactonase and gluconate kinase,
wherein a), b) and glucose dehydrogenase in c) are NAD.sup.+ dependent.

The present invention relates to a yeast cell, in particular a recombinant yeast cell, the cell lacking enzymatic activity needed for the NADH-dependent glycerol synthesis or the cell having a reduced enzymatic activity with respect to the NADH-dependent glycerol synthesis compared to its corresponding wild-type yeast cell, the cell comprising one or more heterologous nucleic acid sequences encoding an NAD.sup.+-dependent acetylating acetaldehyde dehydrogenase (EC 1.2.1.10) activity. The invention further relates to the use of a cell according to the invention in the preparation of ethanol.

The present invention relates to a yeast cell, in particular a recombinant yeast cell, the cell lacking enzymatic activity needed for the NADH-dependent glycerol synthesis or the cell having a reduced enzymatic activity with respect to the NADH-dependent glycerol synthesis compared to its corresponding wild-type yeast cell, the cell comprising one or more heterologous nucleic acid sequences encoding an NAD.sup.+-dependent acetylating acetaldehyde dehydrogenase (EC 1.2.1.10) activity. The invention further relates to the use of a cell according to the invention in the preparation of ethanol.

The present invention relates to a host cell which is capable of producing a dicarboxylic acid and which comprises at least one genetic modification in its genome resulting in the deficiency of at least one enzymatic step catalysing the oxidation of a cofactor. The invention also relates to a process for producing a dicarboxylic acid, which method comprises fermenting such a host cell in a suitable fermentation medium and producing the dicarboxylic acid.

The present invention provides for a mechanism to completely replace the electron accepting function of glycerol formation with an alternative pathway to ethanol formation, thereby reducing glycerol production and increasing ethanol production. In some embodiments, the invention provides for a recombinant microorganism comprising a down-regulation in one or more native enzymes in the glycerol-production pathway. In some embodiments, the invention provides for a recombinant microorganism comprising an up-regulation in one or more enzymes in the ethanol-production pathway.

The invention relates to a recombinant cell, preferably a yeast cell comprising: a) one or more heterologous genes encoding a glycerol dehydrogenase activity; b) one or more genes encoding a dihydroxyacetone kinase (E.C. 2.7.1.28 and/or E.C. 2.7.1.29); c) one or more heterologous genes encoding a ribulose-1,5-biphosphate carboxylase oxygenase (EC 4.1.1.39, RuBisCO); and d) one or more heterologous genes encoding a phosphoribulokinase (EC 2.7.1.19, PRK); and optionally e) one or more heterologous genes encoding for a glycerol transporter. This cell can be used for the production of ethanol and advantageously produces little or no glycerol.

Provided is a recombinant Saccharomyces cerevisiae for producing 2,3-butanediol, wherein all GPD1 and GPD2 genes involved in glycerol biosynthesis are removed and a gene encoding NADH oxidase is introduced, and wherein pyruvate decarboxylase activity is inactivated and Candida tropicalis PDC1 gene encoding Candida tropicalis pyruvate decarboxylase 1-is introduced, and wherein expression of the Candida tropicalis PDC1 gene is regulated by a GPD2 promoter.