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: 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: 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: 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.