A bacterium for producing L-amino acid has improved expression of a polynucleotide encoding a protein represented by SEQ ID NO:3 and improved expression of a polynucleotide encoding a protein represented by SEQ ID NO:31, and/or has mutations in bases at positions −45 bp and −47 bp of a promotor region represented by SEQ ID NO:57. A polynucleotide, encodes proteins and can be included in a recombinant vector, which can be included in a recombinant strain. These are useful in a method for producing L-amino acid. The polynucleotide encodes a protein which is represented by SEQ ID NO:3 and has arginine at position 334 substituted by a terminator or encodes a protein which is represented by SEQ ID NO:31 and has tyrosine at position 592 substituted by phenylalanine, or is formed by mutations in bases at positions −45 bp and −47 bp of a promotor region represented by SEQ ID NO:57.

Disclosed are methods and reagents for the enzymatic measurement of short-chain fatty acids, having 3 to 6 carbon atoms, in a sample. Methods include the use of recombinant butyrate kinases from multiple species, combined various reagents that includes ATP, to detect butyric acid in different types of samples via measurement of ATP consumption. Disclosed also are the reagents themselves.

An isolated polynucleotide including a promoter region derived from a bacterium of the genus Paracoccus, a recombinant host cell including the isolated polynucleotide, and a method of expressing a target gene by culturing a recombinant host cell comprising a polynucleotide comprising the promoter region and a target gene operably linked to the promoter region, under conditions in which the target gene is expressed.

The present disclosure relates to the field of genetic engineering, especially relates to a xylose-induced genetically engineered bacteria used for producing ectoine as well as a construction method and use thereof. The genetically engineered bacteria is constructed by heterologously expressing the ectABC gene cluster from Halomonas elongata on the E. coli chromosome, using the promoter of xylose transporter coding gene xylF to control the RNA polymerase from T7 bacteriophage, reconstructing a synthesis pathway of ectoine and constructing a plasmid-free system, and enhancing the expression of target genes by a strong promoter T7; the yield of ectoine reached 12-16 g/L after 20-28 h fermentation in shake flask, and reached 35-50 g/L after 24-40 h fermentation in a 5 L fermentor.

The present disclosure relates to a variant of YjeH, which is an inner membrane protein, a microorganism including the same, and a method for producing a target product using the same.

The use of microorganisms to make alpha-functionalized chemicals and fuels, (e.g. alpha-functionalized carboxylic acids, alcohols, hydrocarbons, amines, and their beta-, and omega-functionalized derivatives), by utilizing an iterative carbon chain elongation pathway that uses functionalized extender units. The core enzymes in the pathway include thiolase, dehydrogenase, dehydratase and reductase. Native or engineered thiolases catalyze the condensation of either unsubstituted or functionalized acyl-CoA primers with an alpha-functionalized acetyl-CoA as the extender unit to generate alpha-functionalized β-keto acyl-CoA. Dehydrogenase converts alpha-functionalized β-keto acyl-CoA to alpha-functionalized β-hydroxy acyl-CoA. Dehydratase converts alpha-functionalized β-hydroxy acyl-CoA to alpha-functionalized enoyl-CoA. Reductase converts alpha-functionalized enoyl-CoA to alpha-functionalized acyl-CoA. The platform can be operated in an iterative manner (i.e. multiple turns) by using the resulting alpha-functionalized acyl-CoA as primer and the aforementioned alpha-functionalized extender unit in subsequent turns of the cycle. Termination pathways acting on any of the four alpha-functionalized CoA thioester intermediates terminate the platform and generate various alpha-functionalized carboxylic acids, alcohols and amines with different β-reduction degree.

The invention relates to a method of producing a chromosome-free bacterial cell having surface-displayed nanobodies, comprising: i) degrading native chromosomal DNA in a bacterial cell by expressing an endonuclease in the bacterial cell that is capable of recognition and double-stranded cutting of the native chromosomal DNA, wherein the expression of the endonuclease is under control of an inducible or repressible promoter; and ii) transforming the bacterial cell with recombinant nucleic acid encoding enzymes of one or more biochemical energy pathways, or parts thereof, which provide the chromosome-free bacterial cell with energy. The invention further relates to associated compositions, chromosome-free bacterial cells and treatments.

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.

Genetically engineered bacteria, pharmaceutical compositions thereof, and methods of treating or preventing autoimmune disorders, inhibiting inflammatory mechanisms in the gut, and/or tightening gut mucosal barrier function are disclosed.

The invention describes a process for the production of ethanol from a composition comprising glucose and between 50 μM and 100 mM acetic acid, said process comprising fermenting said composition in the presence of a recombinant yeast which is capable to convert acetic acid anaerobically; maintaining the amount of undissociated acetic acid at a value of at least 50 μM; and recovering the ethanol. Said process is useful for both starch and cellulosic based, acetic acid containing hydrolysates and advantageously results in a greater consumption of acetic acid and thus higher ethanol yields.