Abstract: Provided are lysine decarboxylase polypeptides comprising mutants of SEQ ID NO: 2 and/or fragments thereof. The mutants or fragments have at least 95% sequence identity with SEQ ID NO: 2. Also provided are DNA polynucleotides encoding said lysine decarboxylases, expression vector comprising the DNA polynucleotides, transformants, mutant host cells, methods for the production of lysine decarboxylases, and methods for the production of a lysine-derived product.

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 relates to a long-chain dibasic acid with low content of fatty acid impurity and a method of producing it, in particular to the preparation of a long-chain dibasic acid producing strain by using directed evolution and homologous recombination, and to the fermentation production of a long-chain dibasic acid with low content of fatty acid impurity by using said strain. The invention relates to an isolated mutated CPR-b gene, homologous gene or variant thereof, relative to the GenBank Accession Number AY823228, taking the first base upstream of the start codon ATG as ?1, comprising a base mutation ?322G>A, and taking the first base downstream of the stop codon TAG as 1, comprising mutations 3TUTR.19C>T and 3?UTR.76_77insT.

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 acetyl-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 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 present invention relates to a long-chain dibasic acid with low content of long-chain dibasic acid impurity of shorter carbon chain, to the preparation of a long-chain dibasic acid producing strain by directed evolution of POX gene and homologous recombination, and to the production of a long-chain dibasic acid with low content of long-chain dibasic acid impurity of shorter carbon chain by using the strain. The present invention also relates to a strain containing a mutated promoter, wherein, when a long-chain dibasic acid is produced by fermentation of this strain, the content of the acid impurity of shorter carbon chain in the fermentation product is significantly reduced.

Abstract: Provided are microorganisms genetically modified to overexpress porin polypeptides to enhance the production of lysine and lysine derivatives by the microorganism. Also provided are methods of generating such microorganism, and methods of producing lysine and lysine derivatives using the genetically modified microorganisms.

Abstract: The present invention provides a method for preparing nylon salt, which comprises mixing 1,5-pentanediamine, water and dicarboxylic acid at a temperature of 65 to 120° C. to obtain a nylon salt, wherein the amount of the water is 2% to 12% by weight based on the total weight of the 1,5-pentanediamine and the dicarboxylic acid. The present invention also provides a nylon salt. According to the present method for preparing nylon salt, the incomplete reaction between the 1,5-pentanediamine and the dicarboxylic acid, which is caused by the nylon salt present during the preparation in a solid state, can be avoided; the reaction between the 1,5-pentanediamine and the dicarboxylic acid can be significantly speeded up, and the reaction time is accordingly shorten. Consequently, the content of diamine and dicarboxylic acid remained in the resulting nylon salt is very low. In addition, the final nylon salt product, which present in a solid state, makes it easier to be stored and transported.

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 present invention relates to a method for the purification of cadaverine from an aqueous cadaverine salt composition comprising one or more involatile impurities, the method comprising: (1) mixing the aqueous cadaverine salt composition with one or more bases to provide an aqueous cadaverine composition having a pH of at least about 12; (2) distilling or evaporating the aqueous cadaverine composition to produce an aqueous cadaverine solution, wherein one or more solvents are added to the evaporation/distillation system before the evaporation/distillation stops, and the one or more solvents comprise at least one or more high boiling point (HBP) solvents having a boiling point of at least 185° C. (1 atm); and (3) subjecting the aqueous cadaverine solution to one or more rectification steps to provide a cadaverine product.

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: This invention provides acid decarboxylase-prion subunit fusion polypeptides, nucleic acid sequences, expression vectors, and host cells expression such fusion polypeptides to produce various amino acids and derivatives of the amino acids such as polyamines.

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 present invention discloses a method for producing a long chain dicarboxylic acid by fermentation as well as a fermentation broth, a treated fermentation broth and a wastewater. The salt content in the fermentation broth is controlled to be below 20% by the fermentation method of the present invention. The method for producing a long chain dicarboxylic acid by fermentation provided by the present invention can effectively reduce the amount of alkali used in the fermentation process and the amount of acid used in the subsequent extraction of the long chain dicarboxylic acid, thereby reducing the amount of salt in the whole production process of the long chain dicarboxylic acid. At the same time, the method of the present invention also has many advantages such as shortening the fermentation time, increasing the acid production, reducing the amount of medium, and suitable for the production of various types of long-chain dicarboxylic acids, etc.

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 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 herein is a genetically modified host cell comprising a heterologous nucleic acid encoding a biofilm dispersal polypeptide that decreases intracellular c-di-GMP levels and enhances the production of lysine and lysine derivatives. Further provided are methods of generating such cell and producing lysine and lysine derivatives using the genetically modified host cell.

Abstract: One aspect of the present disclosure relates to a stabilized recombinant expression plasmid vector comprising a polynucleotide encoding an antitoxin gene which expresses a polypeptide that neutralizes a polypeptide toxic to a host cell, the toxic polypeptide being expressed by a toxin gene in the host cell, and a polynucleotide encoding a polypeptide expression product, and the stabilized recombinant expression plasmid vector is derived from a Hafnia alvei autonomously replicable backbone plasmid. Other aspects of the present disclosure relate to a transformant transformed with the stabilized recombinant expression plasmid vector disclosed herein, a method of producing biobased cadaverine using the transformant disclosed herein, and biobased cadaverine prepared by the method disclosed herein. Another aspect of the present disclosure relates to a polyamide formed using biobased cadaverine disclosed herein, and a composition thereof.

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 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.