14 results about "Pyruvate oxidase" patented technology

The invention discloses a genetically engineered bacterium for synthesizing N-acetyl blue as well as a construction method and application of the genetically engineered bacterium. The genetically engineered bacterium is prepared by knocking out a lactic dehydrogenase gene ldh and inserting a phosphoketolase gene xfpK on a knockout site, knocking out a pyruvate oxidase gene poxB and inserting a phosphate transacetylase gene pta on a knockout site of a microorganism for producing N-acetyl blue, and knocking out an aconitase inhibition factor gene acnR, inserting a glutamate dehydrogenase gene gdhA on a knockout site, knocking out a glutamine synthetase adenylation transferase gene glnE, and inserting an alpha-ketoglutarate dehydrogenase inhibition factor gene odhI on a knockout site to obtain the strain. According to the method, the supply of the precursor acetyl coenzyme A is enhanced by introducing a non-oxidative glycolysis pathway, the pH dynamic regulation system balances the metabolic flux, and the double breakthrough of the yield and the carbon recovery rate of the N-acetyl blue is realized by combining a two-stage fermentation process.

The invention provides recombinant Escherichia coli for synthesizing heme and derivatives thereof, and the recombinant Escherichia coli is used for knocking out genes such as pyruvate oxidase poxB, pyruvate formate lyase pflB and porphyrinoperoxidase yfeX and enhancing genes such as phosphoenolpyruvate carboxylase ppc, glycerol transporter glpF and 3-phosphoglycerol dehydrogenase glpD, so that the heme and the derivatives thereof can be synthesized. After genes such as exogenous 5-aminolevulinic acid synthase hemA and ferrous chelating enzyme hemH are introduced, the heme and the derivatives thereof can be synthesized by taking glycerol as a raw material, and the heme has an application prospect in the field of biological manufacturing.

This invention discloses a periodontitis-targeted antibacterial supramolecular material, its preparation method, and its application. It belongs to the field of catalyst technology. The preparation method of the periodontitis-targeted antibacterial supramolecular material includes the following steps: dissolving 2,5-dihydroxyterephthalic acid and tetrakis(4-aminophenyl)porphyrin in a first solvent, adding a first catalyst to react, and obtaining a DHA-TAPP COF skeleton; dispersing the DHA-TAPP COF skeleton in a second solvent, adding 3-bromopropyltrimethylammonium bromide and a second catalyst to react, and obtaining Q-COF; dispersing Q-COF in a third solvent, mixing it with H2PtCl6 solution, and then placing it under light conditions to obtain Pt-Q-COF; dispersing Pt-Q-COF in a buffer solution, adding pyruvate oxidase for adsorption treatment, and obtaining POx-Pt-Q-COF. This invention achieves a synergistic effect of "targeted enrichment - dual ROS generation - closed-loop H2O2 supply" through material structure design and functional unit integration, thereby improving the clearance efficiency of periodontal pathogens while ensuring biocompatibility.

The invention discloses a periodontitis-targeted antibacterial supramolecular material and a preparation method and application thereof, and belongs to the technical field of catalysts.The preparation method of the periodontitis-targeted antibacterial supramolecular material comprises the following steps that 2, 5-dihydroxy terephthalic acid and tetra (4-aminophenyl) porphyrin are dissolved in a first solvent, stirring is carried out, and a mixture is obtained; a first catalyst is added for a reaction, and a DHA-TAPP COF skeleton is obtained; the DHA-TAPP COF skeleton is dispersed in a second solvent, 3-bromopropyl trimethyl ammonium bromide and a second catalyst are added for a reaction, and Q-COF is obtained; the Q-COF is dispersed in a third solvent and mixed with an H2PtCl6 solution, then the mixture is placed under the illumination condition, and Pt-Q-COF is obtained; the Pt-Q-COF is dispersed in a buffer solution, pyruvate oxidase is added for adsorption treatment, and the POx-Pt-Q-COF is obtained. Through material structure design and functional unit integration, the synergistic effect of targeting enrichment, double ROS generation and closed-loop H2O2 supply is achieved, the periodontal pathogenic bacterium removal efficiency is improved, and meanwhile the biocompatibility is guaranteed.

The present application provides a recombinant E. coli for synthesizing heme and derivatives thereof, wherein the recombinant E. coli is knocked out of genes such as pyruvate oxidase poxB, pyruvate formate-lyase pflB and protoporphyrinogen peroxidase yfeX, and meanwhile, the genes such as phosphopyruvate carboxylase ppc, glycerol transporter glpF and 3-phosphoglycerate dehydrogenase glpD are enhanced, and the genes such as 5-aminovaleryl-CoA synthase hemA and ferrous chelatase hemH are introduced, so that the recombinant E. coli can synthesize heme and derivatives thereof by using glycerol as a raw material, and has application prospects in the field of biological manufacturing.

The invention discloses a construction method and application of escherichia coli capable of producing fumaric acid, and belongs to the technical field of biological engineering. By-product synthesis related genes such as a fumarase coding gene fumA, a lactic dehydrogenase coding gene ldhA and a pyruvate oxidase coding gene poxB are knocked out, so that the yield of fumaric acid is effectively increased, and the content of heteroacid is reduced. On the basis, the expression of Afpyc, Ecppc and EcaceA genes is up-regulated independently or in a combined manner. The genetically engineered bacterium constructed by the invention adopts an aerobic-microaerobic two-stage fermentation strategy in a 5L fermentation tank, the highest yield of fumaric acid reaches 50.2 g / L after fermentation for 60 hours, the glucose conversion rate is 0.48 g / g, and the by-products lactic acid and acetic acid are both controlled to be 4-5g / L. The strain does not need to carry plasmids, so that the risks of antibiotic use and plasmid loss are avoided, and the strain has good industrial application potential.

The invention provides recombinant escherichia coli for synthesizing heme and derivatives thereof. The recombinant escherichia coli is subjected to genetic engineering modification: genes such as pyruvate oxidase (poxB) and the like are knocked out; meanwhile, the expression of genes such as glycerol 3-phosphate dehydrogenase (glpD) and acetyl coenzyme A synthetase (acs) is enhanced; and genes such as exogenous ferrous chelating enzyme (hemH) and the like are introduced. The modified strain can be used for efficiently synthesizing the heme and the derivatives thereof by taking glycerol, acetic acid and the like as raw materials at the same time, and has a wide industrial application prospect in the field of biological manufacturing.

The invention discloses klebsiella pneumoniae for efficiently producing D-pantothenic acid as well as a construction method and application of the klebsiella pneumoniae, and the specific construction method comprises the following steps: by taking wild klebsiella pneumoniae as an original strain, overexpressing a ketopantoic acid hydroxymethyltransferase gene panB, a pantothenic acid synthetase gene panC and a ketopantoic acid reductase gene panE from escherichia coli; the invention relates to related genes for weakening the expression of a valine-pyruvate transaminase gene ilvE and inactivating byproduct synthesis in a host, and the related genes comprise an alpha-acetolactate decarboxylase gene budA, an acetoin reductase gene budC, glycerol dehydrogenase gldA, a pyruvate oxidase gene poxB, a pyruvate formate lyase activating enzyme gene pflB, an ethanol dehydrogenase gene adhE and a lactic dehydrogenase gene ldhA. The constructed klebsiella pneumoniae engineering bacterium can efficiently synthesize D-pantothenic acid by fermenting glucose, and has great application potential and economic value.

The present invention provides engineered pyruvate oxidase polypeptides useful for the conversion of pyruvate, phosphate, and oxygen to acetyl phosphate, carbon dioxide, and hydrogen peroxide, as well as compositions and methods of utilizing these engineered polypeptides.

The invention discloses a pyruvate oxidase stabilizer and application thereof in an alanine detection kit, and belongs to the technical field of medical analysis. According to the pyruvate oxidase stabilizer disclosed by the invention, specific substances in a proper mass percent range are selected and combined, so that the obtained pyruvate oxidase stabilizer can effectively stabilize pyruvate oxidase and also can effectively stabilize catalase; when the alanine fluorescent probe is applied to an alanine detection kit, interference of endogenous pyruvic acid can be effectively eliminated and alanine is converted into pyruvic acid by further selecting a reagent R1, a reagent R2 and a reagent R3 with proper components in the kit, so that the content of alanine is detected. The alanine detection kit provided by the invention is high in detection accuracy, high in sensitivity, simple and convenient to operate and beneficial to being widely applied to in-vitro alanine content detection.

The invention discloses a blood ammonia determination kit. The kit comprises a reagent 1 (R1) and a reagent 2 (R2), the kit is characterized in that the reagent 1 consists of the following components: a buffer solution, inorganic salt, glutamic acid, ATP, TOOS, peroxidase, glutamine synthetase, pyruvate oxidase, pyruvic acid and a preservative; the reagent 2 is prepared from the following components: a buffer solution, a surfactant, MBTH, a deoxidant, BSA and a preservative. The kit disclosed by the invention takes Trinder reaction as a basic principle, develops color in an MBTH + chromogen mode, successfully solves the problem of poor airborne stability by adding a deoxidant and stabilizing MBTH by specific surface activity, and is relatively good in overall performance evaluation result of the reagent.

The present disclosure relates to a sensing composition comprising a pyruvate responsive enzyme and a thiamine pyrophosphate (TPP). In particular, the sensing composition may comprise a pyruvate responsive enzyme (e.g., pyruvate oxidase), a TPP, an optional flavin adenine dinucleotide (FAD), a stabilizer (e.g., albumin), and a redox mediator. The sensing composition forms a sensing layer on a working electrode to form a sensing electrode. The sensing electrode, together with an electrical circuit, may form part of a system for sensing pyruvic acid. The present disclosure further relates to a method for sensing pyruvic acid comprising accumulating a charge derived from the reaction of pyruvic acid with the sensing composition for a set period of time and then measuring a signal from the accumulated charge.

The invention discloses a construction method of an Escherichia coli engineering strain for efficiently synthesizing xylitol by using various carbon sources such as glucose, cane sugar and the like. The engineering strain realizes the target function through the following genetic modification: knocking out endogenous genes such as pyruvate oxidase poxB and the like, overexpressing key enzyme genes such as phosphoenolpyruvate synthetase ppsA and the like, and introducing heterologous genes such as exogenous xylitol-5-phosphate dehydrogenase and the like. The modified strain shows excellent xylitol synthesis capability, and has important application prospects in the fields of biological manufacturing, food raw material production and the like.