The present invention relates to a genetically engineered microorganism expressing (i) formate tetrahydrofolate (THF) ligase, methenyi-THF cyclohydrolase and methylene-THF dehydrogenase, (ii) the enzymes of the glycine cleavage system (GCS), (iii) serine deaminase and serine hydroxymethyltransferase (SHMT), (iv) an enzyme increasing the availability of NADPH, and (v) optionally formate dehydrogenase (FDH), and wherein the genetically engineered microorganism has been genetically engineered to express at least one of the enzymes of (i) to (v), wheren said enzyme is not expressed by the corresponding microorganism that has been used to prepare the genetically engineered microorganism, and wherein the enzymes of (i) to (v) are genomically expressed.

Provided in this disclosure, in some embodiments, are methods and compositions for treating maple syrup urine disease (MSUD) and other conditions characterized by excessive branched-chain amino acids.

The present invention relates to recombinant microorganisms comprising at least one nucleic acid molecule encoding a ketol-acid reductoisomerase (KARI) or modified NADH-dependent variant thereof, wherein said KARI is at least about 60% identical to SEQ ID NO: 2. In various aspects of the invention, the recombinant microorganisms may comprise an isobutanol producing metabolic pathway and can be used in methods of making isobutanol.

The present application relates to a novel promoter and a method for producing a desired substance using the same.

Metabolites produced by a microorganism using oxaloacetate, pyruvate and/or acetyl-CoA as substrate or co-substrate upstream in the biosynthesis pathway, and more particularly using oxaloacetate. There is indeed a need in the art for transformed, in particular recombinant, microorganisms having at least an increased ability to produce oxaloacetate, pyruvate and/or acetyl-CoA, and in particular oxaloacetate, thus allowing an increased capacity to produce metabolites produced using oxaloacetate, pyruvate and/or acetyl-CoA as substrate or co-substrate upstream in the biosynthesis pathway, and in particular amino acids and their derivatives thereof, fatty acids, derivatives from the mevalonate pathway (in particular farnesyl, squalene, lanosterol, cholesterol and derivatives, and dolichols), flavonoides and/or polyketides. The solution proposed is the use of a genetically modified yeast comprising many modifications as described in the present text.

Described herein are genetically-engineered organisms comprising synthetic operons for the production of isoprenoids, carotenoids, and retinoids, optimized for use in a hydrocarbonoclastic organism, and methods for the synthesis and extraction of isoprenoids in a biofilm bioreactor comprising the genetically-engineered organisms.

The present disclosure relates to a novel method of producing vanillin and/or derivatives thereof by applying improved biocatalysts. Also provided herein are expression systems for preparing said improved biocatalysts. Moreover provided herewith are novel enzyme mutants, corresponding coding sequences and vectors applicable in the biochemical production of vanillin. The present disclosure further provides recombinant host cells or organisms genetically modified for improved functional expression of biocatalysts, as well as recombinant host cells or organisms useful to produce vanillin.

The present disclosure provides engineered ketoreductase enzymes having improved properties as compared to a naturally occurring wild-type ketoreductase enzyme. Also provided are polynucleotides encoding the engineered ketoreductase enzymes, host cells capable of expressing the engineered ketoreductase enzymes, and methods of using the engineered ketoreductase enzymes to synthesize a variety of chiral compounds.

Screening methods as well as kits for identifying modulators of hydroxysteroid (17-beta) dehydrogenase (HSD17B) family member proteins, such as HSD17B13, are provided. The methods comprise screening molecules for their capacity to modulate the HSD17B family member protein, including inhibiting the HSD17B family member protein, as measured by substrate depletion, product concentration from the HSD17B family member protein substrate conversion or NADH concentration, levels of labeled substrate, luciferin light emission, or combinations thereof. Inhibitors of HSD17B family member proteins identified through the screening methods may be used to treat liver diseases, disorders, or conditions in which the HSD17B family member protein plays a role.

Related are a recombinant microorganism for producing L-valine, a construction method and an application thereof. Through transferring an amino acid dehydrogenase gene and/or activating activity of a transhydrogenase and/or a NAD kinase, reducing power of NADPH in cell is increased, the titer and yield of L-valine generated by Escherichia coli are improved, and the production of L-valine by one-step anaerobic fermentation is achieved.