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.

The present application relates to a novel promoter and a method for producing target materials using the same. More specifically, the present application relates to a novel polynucleotide having promoter activity, a gene expression cassette, and a host cell comprising the same, and a method for producing target materials using the microorganism.

The invention relates to a cell capable of converting one or more pentose sugar and one or more hexose sugar into fermentation product constitutively expressing one or more heterologous or homologous polypeptide having the amino acid sequence set out in SEQ ID NO: 20, or a variant polypeptide thereof having at least 45% identity to SEQ ID NO 20. In an embodiment the heterologous polypeptide has glyoxalase activity.

This invention is aimed at improving an ethanol fermentation ability of a recombinant yeast strain having an ability of assimilating pentose, such as xylose or arabinose. The recombinant yeast strain haying an ability of assimilating pentose is obtained by lowering activity of a gene involved in upstream of glyceraldehyde-3-phosphate in the Embden-Meyerhof pathway.

An acetic acid metabolizing ability of a recombinant yeast strain having xylose-metabolizing ability is to be improved. In such a recombinant yeast strain having xylose-metabolizing ability, the acetaldehyde dehydrogenase gene has been introduced and a gene encoding NADH dehydrogenase involved in reoxidation of cytoplasmic NADH on the mitochondrial outer membrane has been suppressed.

The present invention discloses a genetically engineered bacterium using glucose as a substrate for de novo synthesis of vanillin and an application thereof, which belongs to the technical field of gene recombination and metabolic engineering. The genetically engineered bacterium using the glucose as the substrate for de novo synthesis of vanillin disclosed by the present invention is recombinant Corynebacterium glutamicum modified by chassis microorganisms and including a vanillin synthesis module and a methyl cyclic regeneration module. The genetically engineered bacteria constructed by the present invention are safe and non-toxic, can use the glucose for de novo synthesis of natural vanillin, and is low in production cost, high in yield, and promising in application prospect.

Processes for producing ethanol comprise saccharifying cellulosic material with a cellulolytic enzyme composition and fermenting the saccharified cellulosic material with a fermenting microorganism to produce ethanol. The fermenting organism is Saccharomyces cerevisiae CIBTS1260 (deposited under Accession No. NRRL Y-50973 at the Agricultural Research Service Culture Collection (NRRL), Illinois 61604 U.S.A.) or a fermenting organism that has properties that the same or about the same as that of Saccharomyces cerevisiae CIBTS1260).

Provided is an engineered pathway that can function in a cell-free system, cellular system or a combination thereof to convert a sugar to a chemical or biofuel.

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 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.