A method for producing an L-amino acid such as L-glutamic acid is provided. An L-amino acid is produced by culturing in a culture medium a bacterium belonging to the family Enterobacteriaceae and having an L-amino acid-producing ability, and collecting the L-amino acid from the culture medium and/or cells of the bacterium, wherein the bacterium has been modified to have one or more of the following modifications: (A) modification of reducing the activity of a BudA protein; (B) modification of reducing the activity of a BudB protein; (C) modification of reducing the activity of a BudC protein; (D) modification of reducing the activity of a PAJ_3461 protein; (E) modification of reducing the activity of a PAJ_3462 protein; and (F) modification of reducing the activity of a PAJ_3463 protein.

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 present disclosure relates to an acetohydroxy acid synthase variant in which the feedback inhibition to L-valine is released, a polynucleotide encoding the acetohydroxy acid synthase variant, an expression vector including the polynucleotide, a microorganism producing L-valine including the acetohydroxy acid synthase variant, and a method for producing L-valine using the microorganism.

An improved process for alcohol production includes microbial fermentation using a genetically modified microorganism to produce substantial quantities of aldehydes that are stripped from the fermentation medium and condensed. So produced aldehydes are converted in an ex vivo process to corresponding alcohols.

Presented herein are biocatalysts and methods for converting C1-containing materials to organic acids such as muconic acid or adipic acid.

Disclosed are a recombinant yeast for producing 2,3-butanediol and a method for producing 2,3-butanediol using the same. By introducing Candida tropicalis-derived Pdc, which is less active than its own pyruvate decarboxylase (Pdc), into the cells of the strain, the recombinant yeast can synthesize acetyl-CoA, while avoiding production of ethanol, thereby increasing the strain growth rate and the substrate consumption rate and ultimately greatly improving productivity of 2,3-butanediol.

Disclosed is a method for producing 2,3-butanediol. Conventional methods for producing 2,3-butanediol using Saccharomyces cerevisiae (yeast) inevitably cause production of a great amount of glycerol as a by-product, in addition to production of 2,3-butanediol. However, the yeast strain according to the present invention can produce 2,3-butanediol with high purity, high yield and high productivity, while inhibiting production of glycerol.

Various aspects and embodiments herein relate to recombinant proteins with at least one protease recognition sequence, wherein the recombinant proteins can be inactivated by a cognate protease and methods of preparing such proteins. In some embodiments, recombinant phosphoglucose isomerase (Pgi) proteins are provided. In other embodiments, recombinant phosphotransacetylase (Pta) proteins are provided. In yet other embodiments, recombinant transketolase A (TktA) proteins are provided.

The invention provides non-naturally occurring microbial organisms having a (2-hydroxy-3-methyl-4-oxobutoxy)phosphonate pathway, p-toluate pathway, and/or terephthalate pathway. The invention additionally provides methods of using such organisms to produce (2-hydroxy-3-methyl-4-oxobutoxy)phosphonate pathway, p-toluate pathway or terephthalate pathway.

Methods and materials related to producing isobutyric acid are disclosed. Specifically, isolated nucleic acids, polypeptides, host cells, methods and materials for producing isobutyric by direct microbial fermentation from a carbon source are disclosed.

Disclosed is recombinant Escherichia coli for producing L-tyrosine and application thereof, and belongs to the technical fields of genetic engineering and bioengineering. According to the present disclosure, genes aroP and tyrP are knocked out, expresses the endogenous gene yddG of E. coli, then heterologously expresses fpk from Bifidobacterium adolescentis, expresses the endogenous genes ppsA and tktA of E. coli, and then expresses aroG.sup.fbr and tyrA.sup.fbr. Knocking out tyrR, trpE and pheA, so that the synthesis flux of L-tyrosine is increased. Finally, an endogenous gene poxB is knocked out to realize stable fermentation performance at high glucose concentration.