This Invention discloses a method for production of N-Acetyl-D-Glucosamine and/or D-Glucosamine Salt by microbial fermentation. The method is intended to manufacture N-Acetyl-D-Glucosamine and/or D-Glucosamine Salt in higher efficiency and higher yield, by increasing the effects of N-Acetyl-D-Mannosamine Kinase.

A genetically engineered bacterial strain that produces N-acetylglucosamine, as well as a method of construction and use thereof. The genetically engineered bacterial strain can ferment N-acetylglucosamine under a condition of 40-50° C. Through knocking out genes for glucosamine 6-phosphate deaminase, N-acetylglucosamine-6-phosphate deacetylase and the N-acetylglucosamine transporter protein from a parental bacterium, an N-acetylglucosamine catabolism pathway is blocked. Moreover, overexpression genes for glucosamine 6-phosphate synthase and glucosamine 6-phosphate acetylase are introduced, enabling extra cellular accumulation of N-acetylglucosamine and high-temperature fermentation of N-acetylglucosamine at a temperature higher than 40° C.

The disclosure discloses Bacillus subtilis for producing N-acetylneuraminic acid and application thereof, and belongs to the field of genetic engineering. The disclosure optimizes the expression levels of key enzymes in N-acetylneuraminic acid synthesis pathways on genome through promoters of different strength, reduces the protein synthesis pressure caused by the expression of enzymes on cells, and further integrates the three N-acetylneuraminic acids in a same Bacillus subtilis engineering strain. Bacillus subtilis with improved N-acetylneuraminic acid production is obtained, and the production reaches 10.4 g/L at the shake flask level, laying a foundation for further improving the NeuAc production from Bacillus subtilis.

This Invention discloses a method for production of N-Acetyl-D-Glucosamine and/or D-Glucosamine Salt by microbial fermentation. The method is intended to manufacture N-Acetyl-D-Glucosamine and/or D-Glucosamine Salt in higher efficiency and higher yield, by expression of vitreoscilla hemoglobin in microorganism.

The present invention discloses a process for producing N-acetyl-D-glucosamine and D-glucosamine salts by microbial fermentation. The invention includes a method to produce N-acetyl-D-glucosamine and/or D-glucosamine salts with higher efficiency and higher yield by increasing the effect of N-acetyl-D-aminomannose-6-phosphate epimerase in microorganisms.

A method for preparing glucosamine includes the steps of converting fructose-6-phosphate (F6P) and an ammonium salt to glucosamine-6-phosphate (GlcN6P) under the catalysis of glucosamine-6-phosphate deaminase (EC 3.5.99.6, GlmD); and producing glucosamine (GlcN) by the dephosphorylation of GlcN6P under the catalysis of an enzyme capable of catalyzing the dephosphorylation. Such a method can be used to prepare glucosamine by in vitro enzymatic biosystem.

The disclosure discloses Bacillus subtilis for producing N-acetylneuraminic acid and application thereof, and belongs to the field of genetic engineering. The disclosure optimizes the expression levels of key enzymes in N-acetylneuraminic acid synthesis pathways on genome through promoters of different strength, reduces the protein synthesis pressure caused by the expression of enzymes on cells, and further integrates the three N-acetylneuraminic acids in a same Bacillus subtilis engineering strain. Bacillus subtilis with improved N-acetylneuraminic acid production is obtained, and the production reaches 10.4 g/L at the shake flask level, laying a foundation for further improving the NeuAc production from Bacillus subtilis.

This Invention discloses a method for production of N-Acetyl-D-Glucosamine and/or D-Glucosamine Salt by microbial fermentation. The method is intended to manufacture N-Acetyl-D-Glucosamine and/or D-Glucosamine Salt in higher efficiency and higher yield, by increasing the effects of N-Acetyl-D-Mannosamine Kinase.

The present invention discloses a process for producing N-acetyl-D-glucosamine and D-glucosamine salts by microbial fermentation. The invention includes a method to produce N-acetyl-D-glucosamine and/or D-glucosamine salts with higher efficiency and higher yield by increasing the effect of N-acetyl-D-aminomannose-6-phosphate epimerase in microorganisms.

This Invention discloses a method for production of N-Acetyl-D-Glucosamine and/or D-Glucosamine Salt by microbial fermentation. The method is intended to manufacture N-Acetyl-D-Glucosamine and/or D-Glucosamine Salt in higher efficiency and higher yield, by expression of vitreoscilla hemoglobin in microorganism.