A method for preparing glycine by using threonine relates to a fermentation process in which threonine is decomposed into glycine and acetaldehyde by aldolase. Glycine and acetyl coenzyme A can be produced in a fermentation process, in which acetaldehyde is reduced into acetyl coenzyme A or an acetyl coenzyme A derivative by acetylating acetaldehyde dehydrogenase; or threonine is dehydrogenated by threonine dehydrogenase to obtain 2-amino-3-ketobutyric acid, which is then ligated by 2-amino-3-ketobutyrate CoAligase to obtain acetyl coenzyme A. Coenzyme A can be converted into an acetyl coenzyme A derivative under different fermentation conditions.

The present disclosure provides a genetically engineered probiotic, including an exogenous expression cassette including a nucleotide sequence that encodes acetaldehyde dehydrogenase, wherein the probiotic intestinal bacterium is Escherichia coli strain Nissle 1917 (EcN), and uses thereof.

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.

Cell that is genetically modified comprising: a) one or more nucleotide sequence encoding a NAD.sub.+-dependent acetylating acetaldehyde dehydrogenase (E.C. 1.2.1.10); b) one or more nucleotide sequence encoding a acetyl-CoA synthetase (E.C. 6.2.1.1); c) one or more nucleotide sequence encoding a glycerol dehydrogenase (E.C. 1.1.1.6); and d) one or more nucleotide sequence encoding a dihydroxyacetone kinase (E.C. 2.7.1.28 or E.C. 2.7.1.29).

Cell that is genetically modified comprising: a) one or more nucleotide sequence encoding a NAD+-dependent acetylating acetaldehyde dehydrogenase (E.C. 1.2.1.10); b) one or more nucleotide sequence encoding a acetyl-CoA synthetase (E.C. 6.2.1.1); c) one or more nucleotide sequence encoding a glycerol dehydrogenase (E.C. 1.1.1.6); and d) one or more nucleotide sequence encoding a dihydroxyacetone kinase (E.C. 2.7.1.28 or E.C. 2.7.1.29).

A recombinant yeast cell, fermentation compositions, and methods of use thereof are provided. The recombinant yeast cell includes at least one heterologous nucleic acid encoding one or more polypeptide having phosphoketolase activity; phosphotransacetylase activity; and/or acetylating acetaldehyde dehydrogenase activity, wherein the cell does not include a heterologous modified xylose reductase gene, and wherein the cell is capable of increased biochemical end product production in a fermentation process when compared to a parent yeast cell.

The invention provides a non-naturally occurring microbial organism having an adipate, 6-aminocaproic acid or caprolactam pathway. The microbial organism contains at least one exogenous nucleic acid encoding an enzyme in the respective adipate, 6-aminocaproic acid or caprolactam pathway. The invention additionally provides a method for producing adipate, 6-aminocaproic acid or caprolactam. The method can include culturing an adipate, 6-aminocaproic acid or caprolactam producing microbial organism, where the microbial organism expresses at least one exogenous nucleic acid encoding an adipate, 6-aminocaproic acid or caprolactam pathway enzyme in a sufficient amount to produce the respective product, under conditions and for a sufficient period of time to produce adipate, 6-aminocaproic acid or caprolactam.

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 transformed strain having ethanol production potential, constructed by introducing a foreign gene for ethanol production into a non-ethanol producing acetogen Eubacterium limosum and a method for producing ethanol, using the strain. According to the present invention, Eubacterium limosum which is a conventional acetogen lacking ethanol production potential is used to produce ethanol, which is a high value-added product, as a single product from carbon monoxide contained in waste gas.

The present invention provides microorganisms capable of converting acetyl-coA into crotyl alcohol as well as fermentation methods for producing crotyl alcohol, either alone, or in combination with acetone and/or isopropanol. The microorganisms may be genetically engineered to express and/or disrupt one or more of the following enzymes: acetaldehyde dehydrogenase, alcohol dehydrogenase, bifunctional acetaldehyde/alcohol dehydrogenase, aldehyde oxidoreductase, phosphotransacetylase, acetate kinase, CoA-transferase A, CoA-transferase B, acetoacetate decarboxylase, secondary alcohol dehydrogenase, butyryl-CoA dehydro genase (BCD), and/or trans-2-enoyl-CoA reductase (TER).