The invention discloses a glutamate dehydrogenase mutant and an application thereof. The mutant is one of the following: a mutant of the amino acid sequence of SEQ ID NO. 1 which has a mutation at lysine at position 402 to phenylalanine or aspartic acid; a mutant which has a mutation at isoleucine at position 406 to phenylalanine or threonine; a mutant which has a mutation at threonine at position 121 and leucine at position 123; a mutant which has a mutation at alanine at position 379 and leucine at position 383. In the invention, the catalytic activity of glutamate dehydrogenase derived from Pseudomonas putida to 2-carbonyl-4-(hydroxymethylphosphonoyl)butanoic acid (PPO) is significantly improved by a molecular transformation method combining directed evolution and a semi-rational design; and the issue of low glutamate dehydrogenase activity in the process of preparing L-glufosinate by reductive amination is solved.

A method of producing high-purity hydroxy-L-pipecolic acids that includes allowing an L-pipecolic acid hydroxylase, a microorganism or cell having the ability to produce the enzyme, a processed product of the microorganism or cell, and/or a culture liquid comprising the enzyme and obtained by culturing the microorganism or cell, to act on L-pipecolic acid as a substrate in the presence of 2-oxoglutaric acid and ferrous ion, wherein the L-pipecolic acid hydroxylase (1) acts on L-pipecolic acid in the presence of 2-oxoglutaric acid and ferrous ion to add a hydroxy group to the carbon atom at positions 3, 4, and/or 5 of L-pipecolic acid; and (2) has a catalytic efficiency (kcat/Km) with L-proline that is equal to or less than 7 times the catalytic efficiency (kcat/Km) with L-pipecolic acid.

A method for producing an active-form mutant enzyme, by specifying a protein of which a native form exhibits an enzyme activity but which has 10% or less enzyme activity of the native form when a gene of the protein is expressed to provide an inactive-form enzyme; determining a sequence conservation of amino acid residues in an amino acid sequence of the inactive-form enzyme and specifying amino acid residue(s) for which sequence conservation in the inactive-form enzyme is lower than sequence conservation of other amino acid(s) of the same residue; preparing a gene having a base sequence that codes for the amino acid sequence of the inactive-form enzyme in which at least one said specified amino acid residue is substituted by another amino acid with a higher sequence conservation; and expressing the gene to obtain an enzyme that exhibits an enzyme activity of the native form protein.

Provided are Corynebacterium glutamicum that produces L-lysine, a method for constructing the L-lysine producing strain, and a method for producing L-lysine from the strain. The lysine yield and glucose conversion of the L-lysine producing strain are improved, thereby reducing the production cost.

Methods and materials related to producing aspartic acid, β-alanine and salts of each thereof are disclosed. Specifically, isolated nucleic acids, polypeptides, host cells, methods and materials for producing aspartic acid by direct fermentation from sugars are disclosed.

Disclosed are a machine learning gene mining method and a phosphinothricin dehydrogenase mutant for amino translocation. The phosphinothricin dehydrogenase mutant for amino translocation is obtained by mutation of a wild-type phosphinothricin dehydrogenase with an amino acid sequence as shown in SEQ ID No.2 at one of the following sites: (1) E263D-K134R-H96A-R290V; (2) E263D-K134R-H96A; (3) E263D-K134R; (4) E263D; (5) E263N; (6) E263C; and (7) E263G. The present invention utilizes the site-saturation mutagenesis technology to mutate a phosphinothricin dehydrogenase gene as shown in SEQ ID No. 1, finds that the 263rd, 134th, 290th and 290th positions are the key sites affecting enzyme activity and stereoselectivity, and obtains a mutant with enzyme activity and ee value much higher than those of the parent phosphinothricin dehydrogenase.

A method of the bio-production of methionine and/or of its derivatives thereof from a reduced source of sulfur, such as MeSH or MeSNa including genetically modified yeasts, having an increased ability to produce methionine and/or its derivatives thereof, as compared to the parent yeasts.

The present invention refers to a modified glutamate dehydrogenase (GluDH). In particular the modified GluDH of the present invention has an increased activity for catalyzing the reaction of 4-(hydroxymethylphosphinyl)-2-oxobutanoic acid (PPO) and an amino donor to generate L-glufosinate and/or an improved dynamic property. The present invention also refers to the polynucleotide encoding the modified GluDH of the present invention, the vector and host cell for expressing the modified GluDH of the present invention and the method of producing L-glufosinate with the modified GluDH and host cell of the present invention.

Provided is an immobilized enzyme, a preparation method and use thereof. The immobilized enzyme includes an enzyme and an amino resin carrier for immobilizing the enzyme, and the enzyme is selected from any one of the following enzymes: transaminase, ketoreductase, monooxygenase, ammonia-lyase, ene reductase, imine reductase, amino acid dehydrogenase, and nitrilase. The amino resin carrier is an amino resin carrier modified by a cross-linking agent, and the cross-linking agent is a cross-linking agent treated by a polymer. By means of modifying the amino resin carrier with the cross-linking agent treated by the polymer, the enzyme immobilized on the amino resin carrier may easily form a network cross-linking, such that the immobilization effect of the enzyme is more stable, thereby the recycling efficiency of the enzyme is improved.

The present disclosure provides compositions and methods for rapid production of chemicals in genetically engineered microorganisms in a large scale. Also provided herein is a high-throughput metabolic engineering platform enabling the rapid optimization of microbial production strains. The platform, which bridges a gap between current in vivo and in vitro bio-production approaches, relies on dynamic minimization of the active metabolic network.