Provided are a lysine decarboxylase immobilized cell and preparation method thereof.

Provided is a non-naturally occurring microorganism capable of producing cadaverine, wherein the microorganism is genetically modified to overexpress lysine decarboxylase and pyridoxal kinase. Also provided is a method for producing cadaverine by using such microorganism without adding external pyridoxal 5′-phosphate.

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.

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.

Improved processes for producing bio-based nylon precursors having reduced organic and inorganic impurities are described herein. The processes generally comprise fermenting a microorganism engineered to produce lysine in a modified culture medium having low or reduced inorganic ion content, such as by employing a culture medium having an ammonium dicarboxylate buffering system that is preferably devoid of non-essential inorganic ions, and crystallizing the lysine directly from the spent lysine fermentation supernatant by adding a sufficient amount of a dicarboxylic acid. Such strategies aim to produce lysine dicarboxylate salt crystals that are employable in a downstream bioconversion step for the production of cadaverine dicarboxylate salts having reduced organic and inorganic impurities, which improve their downstream performance, for example in polymeration reactions for polyamide synthesis.

One aspect provided herein relates to lysine decarboxylase polypeptides comprising mutants of SEQ ID NO: 2 (i.e., mutants of Klebsiella oxytoca (K. oxytoca) Ldc) and/or fragments thereof. In certain embodiments, the mutants or fragments thereof may have at least about 95% sequence identity with SEQ ID NO: 2. Another aspect provided herein relates to a DNA polynucleotide comprising one or more lysine decarboxylase nucleotide sequences of mutants of SEQ ID NO: 1 (i.e., mutants of K. oxytoca ldc), fragments thereof, or fragments of SEQ ID NO: 1 (i.e., fragments of K. oxytoca ldc). In certain embodiments, the DNA polynucleotide as disclosed herein may encode one or more lysine decarboxylase polypeptides provided herein. In certain embodiments, the DNA polynucleotide as disclosed herein may encode SEQ ID NO: 2, mutants, and/or fragments thereof. In certain embodiments, the lysine decarboxylase nucleotide sequences provided herein may have at least 95% sequence identity with SEQ ID NO: 1 or SEQ ID NO: 3. Another aspect provided herein relates to expression vectors comprising the DNA polynucleotides described herein used for production of a lysine-derived product. Other aspects provided herein include transformants, mutant host cells, methods for the production of lysine decarboxylases, and methods for the production of a lysine-derived product.

The present disclosure describes the engineering of microbial cells for fermentative production of 1,5-diaminopentane and provides novel engineered microbial cells and cultures, as well as related 1,5-diaminopentane production methods.

The present invention discloses an E. coli engineering bacteria producing 1,5-pentanediamine through a whole cell catalysis and its application. The engineering bacteria according to the present invention, is Escherichia coli (E. coli) strain B or its derivative strains with the overexpression of a lysine decarboxylase gene and a proper expression of a lysine-cadaverine antiporter gene cadB. The engineering bacteria according to the present invention is the engineering bacteria producing 1,5-pentanediamine through the whole cell catalysis constructed from Escherichia coli B derivative strains, which has an overexpression of a lysine decarboxylase gene cadA and a proper expression of the lysine-cadaverine antiporter gene cadB. The present invention further discloses a method of producing a 1,5-pentanediamine catalyzed by the engineering bacteria, the yield and production intensity of 1,5-pentanediamine in bio-based production could be significantly improved through the method, hence it could be applied to mass production and convenient for extending applications.

A mutant lysine decarboxylase produced by replacing at least one of the amino acids in SEQ ID NO:4 with another amino acid.

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.