The present invention relates to a recombinant nucleic acid molecule, a recombinant microorganism, to a method for producing alanine and to the use of the recombinant nucleic acid molecule or the recombinant microorganism for the fermentative production of alanine.

The present disclosure provides modified, transgenic, or genome edited/mutated corn plants that are semi-dwarf and have one or more improved ear traits relative to a control plant, such as increase in ear fresh weight, ear area, ear volume, ear diameter, ear length, ear tip void, number of kernels per ear, single kernel weight, and yield. The modified, transgenic, or genome edited/mutated corn plants comprise a transgene encoding one or more glutamate dehydrogenase (GDH) polypeptides and have a reduced expression of one or more GA20 or GA3 oxidase genes. Also provided are methods for producing the modified, transgenic, or genome edited/mutated corn plants.

The present invention discloses a method for producing a 1,2-amino alcohol compound by utilizing whole-cell transformation, and belongs to the technical field of gene engineering and microorganism engineering. According to the present invention, engineered Escherichia coli co-expresses epoxide hydrolase, alcohol dehydrogenase, -transaminase and glutamate dehydrogenase, is capable of realizing whole-cell catalysis of an epoxide in one step to synthesize a 1,2-amino alcohol compound, and meanwhile, can realize regeneration of coenzyme NADP.sup.+ and an amino doner L-Glu; alcohol dehydrogenase expressed by the engineered Escherichia coli is RBS optimized alcohol dehydrogenase, and such RBS optimization can control the expression quantity of alcohol dehydrogenase, so that the catalysis rate of alcohol dehydrogenase and transaminase can achieve an optimum ratio, to eliminate influence caused by a rate-limiting step in a catalyzing course.

Provided are an L-glutamate dehydrogenase mutant and an application thereof, the mutant mutating the amino acid residue A at position 166 and/or the amino acid residue V at position 376 shown in SEQ ID NO. 1 into a hydrophilic or small sterically hindered amino acid residue, the application performing an amination reaction of 2-oxo-4-(hydroxymethylphosphinyl)butyrate in the presence of an L-amino acid dehydrogenase mutant, an inorganic amino donor, and a reduced coenzyme NADPH, and performing an acidification reaction on the obtained L-glufosinate salt to obtain L-glufosinate. Compared to wild L-glutamate dehydrogenase, the present L-glutamate dehydrogenase mutant has a higher concentration of substrates that can be catalysed when preparing L-glufosinate, thereby increasing the efficiency of the action of the enzyme and reducing reaction costs.

The present invention relates to a process for producing a beer bite ring agent via enzyme catalyzed bioconversion of hop-derived isoalpha acids to dihydro-(rho)-isoalpha acids.

The present invention relates to glutamate dehydrogenase mutants and their application in preparation of L-phosphinothricin. The amino acid sequences of the glutamate dehydrogenase mutants are as shown in SEQ ID NO. 1-9, 11, 13, 15, 17-19 and 22. By means of molecular engineering, mutating the specific alanine in glutamate dehydrogenase substrate-binding pocket into glycine and/or mutating the specific valine in glutamate dehydrogenase substrate-binding pocket into alanine, the present invention has obtained NADPH-specific glutamate dehydrogenase mutants with high enzyme activity in catalyzing the substrate 2-oxo-4-[(hydroxy)(methyl)phosphinoyl]butyric acid or its salt for L-phosphinothricin preparation or NADH-specific glutamate dehydrogenase mutants with catalytic activity toward PPO; this has significantly improved substrate conversion, and increased the product concentration of the L-phosphinothricin preparation process.

The invention discloses a glutamate dehydrogenase mutant and an application thereof. The mutant is one of the following: a mutation of the 402th lysine of the amino acid sequence shown in SEQ ID NO. 1 to phenylalanine or aspartic acid; a mutation of the 406th isoleucine to phenylalanine or threonine; a combined mutation of the 121th threonine and the 123th leucine; a combined mutation of the 379th alanine and the 383th leucine. 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.

The present invention relates to a recombinant nucleic acid molecule, a recombinant micro-organism, to a method for producing alanine and to the use of the recombinant nucleic acid molecule or the recombinant microorganism for the fermentative production of alanine.

The present disclosure discloses a production method of Danshensu, belonging to the technical field of bioengineering. The present disclosure constructs a novel genetic engineering strain co-expressed by three enzymes, which can be applied to the production of optically pure 3-(3,4-dihydroxyphenyl)-2-hydroxypropionic acid. All of the (D/L)--hydroxycarboxylic acid dehydrogenase selected by the present disclosure have the characteristics of poor substrate specificity and strong optical specificity, and can produce optically pure D-danshensu and L-danshensu. Further, the production efficiency of the recombinant strain is improved by knocking out or enhancing the expression of a related gene on the E. coli genome to promote substrate transport and reduce product decomposition. The method for producing Danshensu and -ketoglutaric acid by using the transformation of the recombinant strain according to the present disclosure is simple, has easily available raw materials, few impurities, and has good industrial application prospects.

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.