51 results about "Acetyl phosphate" patented technology

The invention discloses an enzyme for catalyzing formaldehyde to synthesize hydroxyl acetaldehyde and an application thereof. In the invention, through site-directed mutation of BFD, a mutant of the enzyme is found; and by means of the mutant of the enzyme, high-effect polymerization of the formaldehyde is achieved; meanwhile, through F / XPK, generation of acetyl phosphoric acid from the hydroxyl acetaldehyde or 1,3-dihydroxyacetone is achieved; with combination of phosphotransacetylase (Pta), a route from the formaldehyde to acetyl coenzyme A is achieved in three steps with the enzyme, thereby creating a new formaldehyde assimilation route, namely, synthesizing the acetyl coenzyme A from the formaldehyde in three steps. The route is short and is free of carbon loss and ATP input.

The invention relates to a recombinant yeast, a construction method thereof and application thereof for producing tyrosol and a derivative. The recombinant yeast is acquired by introducing an exogenous fructose-6-phosphate phosphoketolase into an engineered yeast cell, and the engineered yeast cell is a yeast cell having a metabolic pathway for the synthesis of tyrosol via erythrose-4-phosphate and phosphoenolpyruvate. It is disclosed for the first time that in the process of expressing the fructose-6-phosphate phosphoketolase in the yeast, fructose-6-phosphate is catalyzed into erythrose-4- phosphate and acetyl phosphate while synthesizing 1,6-fructose diphosphate, xylulose-5-phosphate is catalyzed into glyceraldehydes-3-phosphate and acetyl phosphate, which alters the distribution of carbon metabolism in yeast, and enhances the synthesis of erythrose-4-phosphate, an important intermediate of tyrosol biosynthesis. The metabolic pathway of synthetic tyrosol is optimized, and the yieldof derivatives such as tyrosol and hydroxytyrosol is improved.

The present invention discloses a method for synthesizing glutathione by enzymatic catalysis, comprising the following steps: S1, mixing Upsilon-glutamylcysteine synthetase liquid and glutathione synthetase liquid to obtain mixed liquid A, mixing the mixed liquid A with acetate kinase to obtain mixed liquid B; S2, adding an immobilized carrier in the mixed liquid B, stirring for immobilizing, and filtering to obtain an immobilized enzyme; S3, blending glutamic acid, L-cysteine, glycine, magnesium sulfate, ATP (adenosine triphosphate) and acetyl phosphate into a reaction liquid, adding the immobilized enzyme, and stirring for reacting; S4, after reacting, filtering the reaction liquid, and extracting and refining filtrate to obtain the glutathione. The method of the invention has high synthetic efficiency, the production content of the reaction liquid is higher than 10 g / L, and substrate conversion rate reaches higher than 90%; by introducing acetate kinase to construct an ATP regeneration and coupling system, ATP charge is greatly reduced and production cost is significantly reduced; the immobilized enzyme is reusable and highly stable.

Provided herein are compositions and methods for improved production of acetyl-CoA and acetyl-CoA derived compounds in a host cell. In some embodiments, the host cell is genetically modified to comprise a heterologous nucleotide sequence encoding a phosphoketolase (PK), and a functional disruption of an endogenous enzyme that converts acetyl phosphate to acetate. In some embodiments, the host cell further comprises a heterologous nucleotide sequence encoding a phosphotransacetylase (PTA). In some embodiments, the enzyme that converts acetyl phosphate to acetate is a glycerol-1-phosphatase. In some embodiments, the glycerol-1-phosphatase is GPP1 / RHR2. In some embodiments, the glycerol-1-phosphatase is GPP2 / HOR2. The compositions and methods described herein provide an efficient route for the heterologous production of acetyl-CoA-derived compounds, including but not limited to, isoprenoids, polyketides, and fatty acids.

A recombinant yeast is constructed by introducing an expressed gene of exogenous Fructose-6-phosphate phosphoketolase into a modified yeast cell, and the modified yeast cell is a yeast cell with a metabolic pathway for synthesizing tyrosol via Erythrose-4-phosphate and phosphoenolpyruvate. The present invention discloses for the first time that in the process of expressing Fructose-6-phosphate phosphoketolase in a yeast, Fructose-6-phosphate is synthesized into beta-D-Fructose 1,6-bisphosphate and also catalyzed into Erythrose-4-phosphate and Acetyl-phosphate, and Xylulose-5-phosphate is catalyzed into Glyceraldehydes-3-phosphate and Acetyl-phosphate, which change the metabolic flux distribution of carbon in the yeast, enhance the synthesis of Erythrose-4-phosphate as an important intermediate for the biosynthesis of tyrosol, optimize the metabolic pathway for synthesizing tyrosol, and increase the yields of tyrosol and its derivatives such as hydroxytyrosol.

The invention relates to a preparation method of glutamine dipeptide. Escherichia coli is used for expressing amino acid ligase from bacillus subtilis and acetokinase from clostridium acetobutylicum respectively, and a double-enzyme coupling system is formed through mixing after purification. The amino acid ligase is used for catalyzing L-alanine and L-glutamine to generate the glutamine dipeptide, meanwhile ADP is formed along with ATP dephosphorylation, and the acetokinase is used for catalyzing acetyl phosphate and the ADP to form ATP, so that cyclic regeneration of the ATP is realized. By using the double-enzyme coupling system, 32.5 mM of glutamine dipeptide can be obtained through reaction for 8 h under appropriate reaction conditions, and the molar conversion rate is 64.5%. The production method of the glutamine dipeptide provided by the invention has the advantages of low raw material cost, short enzymatic conversion time, simple and convenient operation, low production cost and the like, and has relatively high industrial application value.

The invention relates to an amino acid diagnosis / measurement reagent (kit) utilizing an enzyme-colorimetry method and an enzyme immunoassay technology, and relates to a method for measuring the concentration of amino acid as well as the composition and the components of the reagent, belonging to the technical field of medical / food / environmental detection and measurement. The reagent (kit) mainly comprises the components of buffer solution, NADH, sodium bicarbonate (carbon dioxide), acetyl phosphate, taurine, amino acid oxidase, pyruvic oxidase, taurine dehydrogenase and a stabilizer. The concentration of amino acid is measured by the steps of mixing a sample with the reagent in a certain volume radio to carry out a series of enzymatic reaction, placing the reactants under an ultraviolet / visible light analyzer, and detecting the reducing degree of absorbance at the main wavelength of 340 nm.

The invention relates to a monoamine oxidase diagnosis kit using the technology of an enzyme colorimetric method and an ELISA method, a method for determining monoamine oxidase activity concentration and composition and components of a reagent, and belongs to the technical field of medical test and determination. The kit comprises the following main components: buffer solution, coenzyme, amines, sodium bicarbonate (carbon dioxide), acetyl phosphate, glyceraldehyde-3-phosphoric acid, pyruvate oxidase, glyceraldehyde-3-phosphate dehydrogenase and a stabilizer. The method comprises the following steps: mixing a sample and the reagent according to a certain volume ratio to perform a series of enzymic reaction, and then placing reactants under a UV / visible light analyzer to test the ascending speed of absorbance at the position where the dominant wave length is 340nm to determine the activity concentration of the monoamine oxidase.

The invention discloses a genetically engineered bacterium that weakens the accumulation of acetic acid in the fermentation process to enhance the production of L-tryptophan and a construction method thereof, belonging to the fields of metabolic engineering and genetic engineering. The present invention takes L-tryptophan production strain (recombinant Escherichia coli) FB-04 (referred to as TS) phosphate acetyltransferase (Pta) as the parent, and uses molecular biology techniques to perform site-directed mutation on it. Under this modification, the specific activity of Pta was 60.4% of that before the mutation. Using Red recombination technology, the pta gene on the TS genome was mutated by a two-step traceless gene replacement method to construct an engineering bacterium TS‑PtaP69L. This strategy significantly reduces the specific activity of Pta, and the engineering bacteria TS-PtaP69L is compared with TS in the fermentation process: 1) The content of tryptophan in shake flask fermentation increases by 80%, and the content of acetic acid decreases by 15.5%; 2) Tryptophan in 3L fermenter fermentation The acid content increased by 12.6%, and the acetic acid content decreased by 73%. The tryptophan mutant strain has better industrial fermentation performance. This genomic site-directed mutagenesis strategy can also be used to improve the fermentation performance of E. coli producing other amino acids.

The invention relates to a monoamine oxidase diagnosis kit using the technology of an enzyme colorimetric method and an ELISA method, a method for determining monoamine oxidase activity concentration and composition and components of a reagent, and belongs to the technical field of medical test and determination. The kit comprises the following main components: buffer solution, reduced coenzyme, amines, sodium bicarbonate (carbon dioxide), acetyl phosphate, pyruvate oxidase, lactate dehydrogenase and a stabilizer. The method comprises the following steps: mixing a sample and the reagent according to a certain volume ratio to perform a series of enzymic reaction, and then placing reactants under a UV / visible light analyzer to test the descending speed of absorbance at the position where the dominant wave length is 340nm to determine the activity concentration of the monoamine oxidase.

Microorganisms comprising modifications for producing pyruvate, ethanol, and other compounds. The microorganisms comprise modifications that reduce or ablate activity of one or more of pyruvate dehydrogenase, 2-oxoglutarate dehydrogenase, phosphate acetyltransferase, acetate kinase, pyruvate oxidase, lactate dehydrogenase, cytochrome terminal oxidase, succinate dehydrogenase, 6-phosphogluconate dehydrogenase, glutamate dehydrogenase, pyruvate formate lyase, pyruvate formate lyase activating enzyme, and isocitrate lyase. The microorganisms optionally comprise modifications that enhance expression or activity of pyruvate decarboxylase and alcohol dehydrogenase. The microorganisms are optionally evolved in defined media to enhance specific production of one or more compounds. Methods of producing compounds with the microorganisms are provided.

The invention relates to a monoamine oxidase diagnostic / measuring reagent (kit) which utilizes enzyme colorimetry and enzyme-linked method technologies, and meanwhile, the invention also relates to a method for measuring monoamine oxidase active concentration and compositions and components of the reagent, which belong to the technical field of medical inspection and measurement. The main components of the reagent (kit) of the invention comprise a buffer solution, reduced coenzyme, an amine compound, sodium bicarbonate (carbon dioxide), acetyl phosphate, taurine, pyruvate oxidase, tauropine dehydrogenase and a stabilizer; and the method comprises the following steps of: enabling a sample and the reagent to generate a series of enzymatic reactions through mixing the sample and the reagent according to a certain volume ratio, then placing the reactants under an ultraviolet / visible light analyzer and detecting the descending speed of the absorbance at a position with the dominant wavelength of 340nm to measure and calculate the active concentration magnitude of monoamine oxidase.

The invention discloses a method for further synthesizing acetyl coenzyme A by reacting glycolaldehyde with 4-erythrose phosphate under the catalysis of aldolase to generate 6-allose phosphate. The method disclosed by the invention is high in catalytic rate, the theoretical carbon yield of a reaction route is 100%, carbon loss is avoided, the 4-erythritol phosphate, the enzyme and the coenzyme can be recycled, and the reaction efficiency is relatively high. The method disclosed by the invention can play more obvious advantages in the production processes of in-vitro continuous multi-enzyme catalysis, fed-batch fermentation, continuous fermentation and the like capable of controlling the substrate level.

Disclosed is a new approach for synthesizing an acetyl coenzyme A and a derivative product thereof (5-phosphoarabinose, acetyl phosphoric acid, acetyl phosphate, and an acetyl coenzyme A derivative compound) using glycolaldehyde. The approach comprises a reaction of glycolaldehyde and 3-phosphoglyceraldehyde under the catalysis of an enzyme to generate 5-phosphoarabinose, wherein the enzyme is selected from an aldolase, a transaldolase, an isoenzyme and a mutant enzyme thereof.

The invention discloses a method for reducing the proportion of by-products of succinic acid fermentation of Actinobacillus succinates, comprising fermenting and culturing the bacteria after activation and propagation of the bacteria, and the inoculation amount is 5-15% by volume. The medium is supplemented with bisulfite or partial sulfite, and the addition amount is 1g / L~20g / L. In the present invention, bisulfite or partial sulfite is added in the process of producing succinic acid by fermentation of Actinomyces succinic acid bacteria, and through addition reaction with the intermediate product acetylphosphoric acid generated in the cell, it is prevented from being further converted into acetic acid, The content of acetic acid by-product can be greatly reduced without affecting the production of succinic acid. The process is simple in operation, low in cost, and has industrial application value.

The invention relates to a monoamine oxidase diagnosis kit using the technology of an enzyme colorimetric method and an ELISA method, a method for determining monoamine oxidase activity concentration and composition and components of a reagent, and belongs to the technical field of medical test and determination. The kit comprises the following main components: buffer solution, coenzyme, amines, sodium bicarbonate (carbon dioxide), acetyl phosphate, coenzyme A, pyruvate oxidase, pyruvate dehydrogenase and a stabilizer. The method comprises the following steps: mixing a sample and the reagent according to a certain volume ratio to perform a series of enzymic reaction, and then placing reactants under a UV / visible light analyzer to test the ascending speed of absorbance at the position where the dominant wave length is 340nm to determine the activity concentration of the monoamine oxidase.