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.

A CRISPR system is successfully used to modify the genomes of a gram-positive bacterium, such as a species of the Cornybacterium genus. Methods for modifying Corynebacterium species include single-nucleotide changes, creating gene deletions and/or insertions.

Provided are a microorganism comprising variant LysE, and an L-amino acid producing method using same. The variant LysE may improve L-amino acid excretion and/or production capacity compared to a wild type.

Provided is a method of preparing a granular feed additive. When the method of preparing a granular feed additive according to one exemplary embodiment is used, it is possible to prepare a granular feed additive including a high content of basic amino acids while preventing hygroscopicity and agglomeration caused by the basic amino acids. In addition, since the method of preparing a granular feed additive according to one exemplary embodiment may omit a process of using hydrochloric acid, which is generally used to neutralize basic amino acids, it is possible to simplify the process and to solve process problems caused by the use of hydrochloric acid.

A method of producing sulfur-containing amino acids or derivatives of the sulfur-containing amino acids.

The biological production of beta-hydroxyisovalerate (βHIV) using a non-natural microorganism. The non-natural microorganism for the biologically-derived βHIV provides more beta-hydroxyisovalerate synthase activity than the wild-type parent. The non-natural microorganism can host a non-natural enzyme, such as the non-natural enzyme expressed in a yeast or bacteria, wherein the non-natural microorganism comprises an active βHIV metabolic pathway for the production of βHIV. The biological derivation of βHIV eliminates toxic by-products and impurities that result from the chemical production of βHIV, such that βHIV produced by a non-natural microorganism prior to any isolation or purification process has not been in substantial contact with any halogen-containing component.

Provided is a method for screening a Corynebacterium constitutive expression vector promoter on the basis of transcriptome sequencing; and further provided are the Corynebacterium constitutive expression vector promoter screened on the basis of transcriptome sequencing, an expression vector comprising the promoter, a recombination strain obtained by transforming a host cell Corynebacterium glutamicum using the expression vector, and applications thereof.

Arginine deiminase (ADI)-containing genetically engineered Corynebacterium glutamicum (C. glutamicum), a fusion protein cipA-arc, use thereof, and a method for preparing [.sup.14/15N]-L-citrulline through enzymatic catalysis are provided. The ADI-containing genetically engineered Corynebacterium glutamicum (C. glutamicum) has a deposit number of CGMCC No. 19404, which expresses a fusion protein cipA-arc. Both the genetically engineered strain and the fusion protein cipA-arc can be used to convert [.sup.14/15N]-L-arginine into [.sup.14/15N]-L-citrulline.

The present invention relates to a Corynebacterium glutamicum mutant strain having increased L-glutamic acid productivity, a method for constructing the same, and a method of producing L-glutamic acid using the same. The Corynebacterium glutamicum mutant strain is a strain into which a mechanosensitive ion channel gene derived from a Corynebacterium sp. strain has been introduced, and thus it can produce L-glutamic acid in an improved yield due to enhancement of glutamic acid release. Therefore, when the mutant strain is used, it is possible to more effectively produce L-glutamic acid.

The present disclosure relates to an acetohydroxy acid synthase variant, a polynucleotide encoding the variant, a microorganism including the variant, and a method of producing L-isoleucine using the microorganism.