The present invention relates to the field of biotechnology engineering. It provides a method of constructing a recombinant Bacillus subtilis that can produce specific-molecular-weight hyaluronic acids. By integranted expression of hasA from Streptococcus zooepidemicus and overexpression of genes of HA synthetic pathway, tuaD, glmU and glmS, high yield HA production was achieved in the recombinant strain. Additionally, introduction and functional expression of the leech hyaluronidase in the recombinant strain substantially increased the yield of HA to 19.38 g.Math.L.sup.1. Moreover, HAs with a broad range of molecular weights (10.sup.3 Da to 10.sup.6 MDa) were efficiently produced by controlling the expression level of hyaluronidase using RBS mutants with different translational strengths. The method of the present invention can be used to produce low molecular weight HAs at large scale in industrial applications.

An isolated nucleic acid molecule is provided comprising a nucleotide sequence which encodes a glutamine:fructose-6-phosphate amidotransferase from E. coli which is particularly suitable for expression in cotton plant cells. The invention also relates to plant cells or plants, in particular to cotton plant cells or cotton plants which produce an increased amount of positively charged polysaccharides in their cell walls. Furthermore methods and means are provided to increase the content of positively charged polysaccharides in the cell walls of cotton cells, in particular in cotton fibers. Fibers obtained from such cotton plants have an altered chemical reactivity which can be used to attach reactive dyes or other textile finish reagents to these fibers.

The present invention relates to the field of biotechnology engineering. It provides a method of constructing a recombinant Bacillus subtilis that can produce specific-molecular-weight hyaluronic acids. By integranted expression of hasA from Streptococcus zooepidemicus and overexpression of genes of HA synthetic pathway, tuaD, glmU and glmS, high yield HA production was achieved in the recombinant strain. Additionally, introduction and functional expression of the leech hyaluronidase in the recombinant strain substantially increased the yield of HA to 19.38 g.Math.L.sup.1. Moreover, HAs with a broad range of molecular weights (10.sup.3 Da to 10.sup.6 MDa) were efficiently produced by controlling the expression level of hyaluronidase using RBS mutants with different translational strengths. The method of the present invention can be used to produce low molecular weight HAs at large scale in industrial applications.

The present invention relates to a method for producing lacto-N-tetraose (LNT) and lacto-N-neotetraose (LNnT) using Corynebacterium glutamicum, and more specifically to: recombinant Corynebacterium glutamicum transformed such that, in order to increase productivity of LNT and LNnT, genes introduced from outside are expressed in Corynebacterium glutamicum, and genes inherent in Corynebacterium glutamicum are overexpressed; and a method for producing LNT and LNnT using same. Accordingly, the present invention uses Corynebacterium glutamicum so as to enable producing LNT and LNnT in a safe manner and in high concentration, high yield, high productivity, compared to when using conventional Escherichia coli.

This disclosure is in the technical field of synthetic biology and metabolic engineering. More particularly, this disclosure is in the technical field of cultivation or fermentation of metabolically engineered cells. This disclosure describes a cell metabolically engineered for production of a mixture of at least three different oligosaccharides. Furthermore, this disclosure provides a method for the production of a mixture of at least three different oligosaccharides by a cell as well as the purification of at least one of the oligosaccharides from the cultivation.

The Corynebacterium glutamicum strain of the present invention is obtained by mutating Corynebacterium glutamicum ATCC 13032, with the mutation sites including: mutating cytosine at site 862902 into thymine; mutating guanine at site 862903 into adenine; mutating cytosine at site 862953 into thymine; mutating adenine at site 862961 into guanine; inserting cytosine and thymine at site 862958; and mutating of guanine at site 862963 by deletion. The Corynebacterium glutamicum strain of the present invention exhibits significantly increased tolerance in high-viscosity environments and growth and metabolism ability under low dissolved oxygen conditions, thereby increasing the yield of mucopolysaccharides, and avoiding the problems where resulting mucopolysaccharides cause the fermentation broth to become viscous and have insufficient dissolved oxygen, which would further limit the metabolism of Corynebacterium glutamicum and ultimately affect the synthesis of mucopolysaccharides.

Production of a mixture of neutral fucosylated oligosaccharides by a cell. The disclosure is in the technical field of synthetic biology and metabolic engineering. More particularly, the disclosure is in the technical field of cultivation or fermentation of metabolically engineered cells. The disclosure describes a cell metabolically engineered for production of a neutral mixture of at least four different neutral fucosylated oligosaccharides. Furthermore, the disclosure provides a method for the production of a neutral mixture of at least four different neutral fucosylated oligosaccharides by a cell as well as the purification of at least one of the neutral oligosaccharides from the cultivation.