Abstract: The present disclosure provides a method and a system for extracting long chain dicarboxylic acid, the method comprising: (1) subjecting a long chain dicarboxylic acid fermentation broth to a primary membrane filtration treatment to give a first filtrate; subjecting the first filtrate to decolorization, acidification/crystallization, and solid-liquid separation treatments to give a first solid; (2) mixing the first solid, a base and water to form a solution; subjecting the solution to a secondary membrane filtration treatment to give a second filtrate; subjecting the second filtrate to decolorization, acidification/crystallization, and solid-liquid separation treatments to give a second solid; and (3) mixing the second solid and water to form a mixture; subjecting the mixture to a thermostatic treatment at 105-150° C., followed by cooling for crystallization and solid-liquid separation treatment.

Abstract: The invention relates to a long-chain dibasic acid with low content of monobasic acid impurity and a production method thereof, in particular to the preparation of a long-chain dibasic acid producing strain by means of directed evolution and homologous recombination, and to the production of a long-chain dibasic acid with low content of monobasic acid impurity by fermentation of said strain. The invention relates to a mutated CYP52A12 gene, homologous gene or variant thereof, which, relative to GenBank Accession Number AY230498 and taking the first base upstream of the start codon ATG as ?1, comprises a mutation. The invention relates to a strain comprising said mutated CYP52A12 gene, homologous gene or variant thereof wherein when the strain is fermented to produce a long-chain dibasic acid, the content of monobasic acid impurity in the fermentation product is significantly reduced.

Abstract: The invention is directed to a method of preparing a long chain dicarboxylic acid producing strain by using directed evolution and homologous recombination, a strain obtained by this method that is capable of producing a long chain dicarboxylic acid under an acidic condition and the use of the strain. In particular, the invention is directed to a method of preparing a long chain dicarboxylic acid producing strain by using directed evolution of CYP52A12 gene and homologous recombination, a strain obtained by this method that is capable of producing a long chain dicarboxylic acid under an acidic condition and the use of the strain.

Abstract: The invention provides microorganisms genetically modified to overexpress thermophilic lysine decarboxylase polypeptides in a mesophilic host to enhance the production of lysine and lysine derivatives by the microorganism, method of generating such microorganism, and methods of producing lysine and lysine derivatives using the genetically modified microorganisms.

Abstract: The present disclosure provides a method and a system for refining long chain dicarboxylic acid, said method comprising the following steps: (1) subjecting a long chain dicarboxylic acid fermentation broth or a treated liquid therefrom to a membrane filtration, an acidification/crystallization, a solid-liquid separation and drying to give a long chain dicarboxylic acid crude product; (2) subjecting the long chain dicarboxylic acid crude product to a vacuum distillation to give the long chain dicarboxylic acid product; wherein the pressure in the vacuum distillation is ?100 Pa. By using the refining method according to the present disclosure, the procedure is simplified, and the purity of the obtained product is high, and the disadvantages such as poor quality of the product obtained by crystallization from a solvent and environment pollution caused by a solvent can be overcome.

Abstract: The present invention relates to a long-chain dibasic acid with low content of hydroxyl acid impurity and a production method thereof, in particular to a method for producing a long-chain dibasic acid with low content of hydroxyl acid impurity by fermenting a long-chain dibasic acid producing strain prepared by homologous recombination method. The present invention relates to a recombinant long-chain dibasic acid producing microorganism, having increased alcohol dehydrogenase activity and optionally decreased acyl-CoA oxidase activity. The present invention also relates to a method of producing a long-chain dibasic acid by the recombinant long-chain dibasic acid producing microorganism and use thereof.

Abstract: The invention provides microorganisms genetically modified to co-overexpress a carbohydrate binding module and lysine decarboxylase polypeptides in a mesophilic host to enhance the production of lysine derivatives by the microorganism, method of generating such microorganism, and methods of producing lysine derivatives using the genetically modified microorganisms.

Abstract: One aspect of the invention relates to a mutant polypeptide comprising the amino acid sequence of Escherichia coli tetracycline efflux pump A (TetA). Another aspect of the invention relates to a polynucleotide encoding a polypeptide of TetA, a fragment thereof, or a mutant thereof. Another aspect of the invention relates to a first expression plasmid vector comprising one or more first polynucleotides encoding a first polypeptide comprising a tetracycline efflux pump polypeptide, a fragment thereof or a mutant thereof, one or more second polynucleotides independently selected from the group consisting of a third polynucleotide encoding a third polypeptide comprising a lysine decarboxylase polypeptide, a fragment thereof or a mutant thereof, and a fourth polynucleotide encoding a fourth polypeptide comprising a lysine biosynthesis polypeptide, a fragment thereof or a mutant thereof.

Abstract: The invention relates to the directed evolution of CYP52A12 gene and the use thereof for the production of a dicarboxylic acid. In particular, it relates to a method of preparing a long chain dicarboxylic acid producing strain by using directed evolution and homologous recombination, a strain obtained by the method that is capable of producing a long chain dicarboxylic acid under an acidic condition and the use thereof. In particular, the invention relates to a method of preparing a long chain dicarboxylic acid producing strain by directed evolution of CYP52A12 gene and homologous recombination, a strain obtained by the method that is capable of producing a long chain dicarboxylic acid under an acidic condition and the use thereof. By directed evolution of CYP52A12 gene, one strain which has a base mutation at the promoter region of said gene and is capable of producing a long chain dicarboxylic acid under an acidic condition in a shortened fermentation time is screened out in the invention.

Abstract: The invention provides CadA polypeptides with mutations that increase activity in alkaline pH compared to the wild-type lysine decarboxylase. The invention also provides methods of generating such mutant polypeptides, microorganisms genetically modified to overexpress the mutant polypeptides, and methods of generating such microorganisms.

Abstract: The invention provides CadA polypeptides with mutations that increase activity in alkaline pH compared to the wild-type lysine decarboxylase. The invention also provides methods of generating such mutant polypeptides, microorganisms genetically modified to overexpress the mutant polypeptides, and methods of generating such microorganism.

Abstract: The invention relates to the directed evolution of CYP52A12 gene and the use thereof for the production of a dicarboxylic acid. In particular, it relates to a method of preparing a long chain dicarboxylic acid producing strain by using directed evolution and homologous recombination, a strain obtained by the method that is capable of producing a long chain dicarboxylic acid under an acidic condition and the use thereof. In particular, the invention relates to a method of preparing a long chain dicarboxylic acid producing strain by directed evolution of CYP52A12 gene and homologous recombination, a strain obtained by the method that is capable of producing a long chain dicarboxylic acid under an acidic condition and the use thereof. By directed evolution of CYP52A12 gene, one strain which has a base mutation at the promoter region of said gene and is capable of producing a long chain dicarboxylic acid under an acidic condition in a shortened fermentation time is screened out in the invention.

Abstract: Provided microorganisms genetically modified to overexpress an imine/enamine deaminase to enhance the production of lysine and lysine derivatives by the microorganism. Also provided a method of generating such microorganism, and methods of producing lysine and lysine derivatives using the genetically modified microorganisms.

Abstract: Provided is a method for purifying 1,5-pentanediamine comprising: providing 1,5-pentanediamine to be purified and treating the 1,5-pentanediamine to be purified by a reduction reaction to obtain purified 1,5-pentanediamine. Meanwhile, further provided is 1,5-pentanediamine prepared by the method. The purification method has a concise process and a simple operation, and is suitable for industrial production, and can significantly improve the quality of 1,5-pentanediamine.

Abstract: The invention provides microorganisms genetically modified to overexpress biofilm dispersal related polypeptides to enhance the production of lysine and lysine derivatives by the microorganism, method of generating such microorganism, and methods of producing lysine and lysine derivatives using the genetically modified microorganisms.

Abstract: The present disclosure provides method for isolating a long chain dicarboxylic acid such as a substantially pure or pure long chain dicarboxylic acid from a fermentation broth containing microbial cells.

Abstract: The present invention provides a decanedioic acid produced by microbial fermentation process, in which the content of C10 aliphatic acid and C10 hydroxy aliphatic acid is maintained at a very low level. The present invention also provides a preparation method of the decanedioic acid and a polymer prepared by using the decanedioic acid as monomer. The decanedioic acid provided by the present invention is prepared by microbial fermentation process. The decanedioic acid product which is produced through the processes of microbial fermentation and separation has a higher purity, a higher thermal stability, and a lower impurity content. The decanedioic acid provided by the present invention could satisfy the requirements of high grade product of polyamide or polyester to produce polymer with excellent qualities.

Abstract: The present disclosure provides a method for isolating a long chain dicarboxylic acid from fermentation broth containing microbial cells. Also provided is a substantially pure long chain dicarboxylic acid isolated by the method.

Abstract: Provided is a method for extracting a 1,5-pentanediamine from a solution system containing a 1,5-pentanediamine salt. The method comprises adding to the solution system an insoluble basic substance to form a solution system containing free 1,5-pentanediamine. The provided method has high applicability, is easy to use, and is environmentally-friendly, significantly lowering raw material costs and operating costs for the entire manufacturing process. The method achieves a high recovery rate for pentanediamine, and is more suitable for industrial-scale production.

Abstract: The invention provides CadA polypeptides with mutations that increase activity in alkaline pH compared to the wild-type lysine decarboxylase. The invention also provides methods of generating such mutant polypeptides, microorganisms genetically modified to overexpress the mutant polypeptides, and methods of generating such microorganism.