Provided is a mutant strain having improved aromatic amino acid production capability as a result of inactivation or weakening of activity of glutaminase which is expressed by glutaminase B (glsB) gene.

Provided are efficient catalyst of engineered enzymes and an economical enzymatic reaction solution to solve the problems in the current production process of L-tyrosine and its derivatives. The method of the invention has the advantages of high product concentration, mild reaction conditions, simple purification process, simple operation, environmental friendliness, and easy industrial scale-up. Thus, it has good industrial application prospects.

The present invention generally relates to the microbiological industry, and specifically to the production of L-serine or L-serine derivatives using genetically modified bacteria. The present invention provides genetically modified microorganisms, such as bacteria, wherein the expression of genes encoding for enzymes involved in the degradation of L-serine is attenuated, such as by inactivation, which makes them particularly suitable for the production of L-serine at higher yield. The present invention also provides means by which the microorganism, and more particularly a bacterium, can be made tolerant towards higher concentrations of serine. The present invention also provides methods for the production of L-serine or L-serine derivative using such genetically modified microorganisms.

The present invention is related to sustainable fermentation processes with increased efficiency and less environmental impact. Particularly, the present invention is related to a process wherein in one fermentation process two or more fermentation products can be produced and isolated, i.e. a “primary” fermentation product and a “secondary” fermentation product, particularly wherein one is a water soluble organic compound and one is a fat-soluble organic compound particularly a fat-soluble vitamin, preferably vitamin K2.

The present invention provides engineered tyrosine ammonia-lyase (TAL) polypeptides and compositions thereof. In some embodiments, the engineered TAL polypeptides have been optimized to provide enhanced catalytic activity while reducing sensitivity to proteolysis and increasing tolerance to acidic pH levels. The invention also provides methods for utilization of the compositions comprising the engineered TAL polypeptides for therapeutic and industrial purposes.

A method of generating a variant cyanobacterium (e.g., Synechococcus elongatus, in particular S. elongatus sp. PCC11801) for photoautotrophic production of an amino acid (e.g., L-phenylalanine); the variant so produced; a method of extending growth of a culture of a variant cyanobacterium and its photoautotrophic production of an amino acid; and a method of photo-autotrophically producing L-phenylalanine.

The present disclosure relates to a variant of cAMP receptor protein of Escherichia coli with alanine at position 35, a microorganism including the same, and a method of producing an L-amino acid using the same.

The present disclosure relates to a variant of cAMP receptor protein of Escherichia coli with alanine at position 35, a microorganism including the same, and a method of producing an L-amino acid using the same.

The present disclosure provides novel bacterial strains with altered expression or start codon modification of one or more RNA degradation/processing genes. The RNA degradation genes of the present disclosure are controlled by heterologous promoters. The present disclosure further describes methods for generating microbial strains comprising heterologous promoter sequences operably linked to RNA degradation/processing genes.

A transport protein coding gene, and a method for efficient production of L-tryptophan by a strain containing the gene. Specifically, by heterologous expression of ywkB gene from Bacillus subtilis on the genome of Escherichia coli, L-tryptophan production efficiency of the strain can be improved. Performing shake flask fermentation with the strain can accumulate 15.2 g/L of L-tryptophan within 24 h, which is 35% higher than a control strain.