39 results about "Oxaloacetic acid" patented technology

The invention belongs to the technical field of biology, and discloses a biosynthesis method of L-homoserine. According to the biosynthesis method, L-homoserine is synthesized by taking L-aspartic acid and formaldehyde as substrates, aldolase and transaminase are adopted, and oxaloacetic acid decarboxylase can be optionally added to improve the efficiency of a catalytic system. The method can be realized through an in-vitro multi-enzyme catalysis system, and can also be completed in a manner of introducing a way into microorganisms. According to the method, methanol, formaldehyde and other carbon resources can be introduced to synthesize the L-homoserine with high value, the raw materials are low in price, and the whole synthesis method has the advantages of high atom utilization rate and high conversion rate.

This invention relates to methods of measuring the activity of a FAMIN protein that comprise determining the aspartate transaminase activity of the FAMIN protein, for example by measuring the consumption of aspartate and / or α-ketoglutarate in the presence of the FAMIN protein and / or the production of oxaloacetate and / or glutamate. Methods of measuring and screening FAMIN activity are provided.

The invention discloses a recombinant genetically engineered bacterium for producing beta-alanine by dynamically regulating and controlling a competitive pathway and application of the recombinant genetically engineered bacterium, heterologous key genes pycCG and NCgl0580 are over-expressed on plasmids, accumulation of a beta-alanine precursor oxaloacetic acid pool is increased, and efflux of beta-alanine is enhanced; a heterologous gene gapN is introduced to adjust a glycolytic pathway, so that the efficiency of the glycolytic pathway is enhanced, and the carbon flow in a beta-alanine synthesis pathway is increased; the expression activity of the gene gltBD is up-regulated so as to enhance the supply of an amino donor when oxaloacetic acid is converted into aspartic acid; an EsaI / EsaR group sensing system is introduced to dynamically regulate and control an aspartic acid competition branch; after the thrA gene promoter is replaced by PesaS, the situation that excessive metabolic flow enters an aspartic acid competition branch is effectively weakened, the carbon flow is pulled to the synthesis direction of beta-alanine to the maximum extent, and the yield of beta-alanine is obviously increased.

The invention provides a genetic engineering strain for efficiently producing beta-alanine, an escherichia coli strain is modified by adopting a genetic engineering means, and a multi-plasmid system is constructed, so that a metabolic pathway is optimized and the product synthesis efficiency is improved. The method comprises the following steps: firstly, by constructing a recombinant plasmid pET-PanD, introducing aspartic acid decarboxylase (L17F / G24R mutant) with mutation so as to promote efficient conversion of aspartic acid to beta-alanine; meanwhile, phosphoenolpyruvate carboxylase (PPC) is overexpressed through the recombinant plasmid pRSF-PPC, generation of oxaloacetic acid (OAA) is increased, and then the synthesis path of carbon flow to beta-alanine is improved. Besides, NADH dependent type aspartate dehydrogenase (AspDH) from pseudomonas aeruginosa is overexpressed by adopting a pBAD-AspDH plasmid, so that the dependence on NADPH is reduced, and the conversion efficiency is further improved.

The invention discloses an artificial synthesis method and application of malonyl coenzyme A. An artificial synthesis route for synthesizing malonyl-CoA by taking beta-alanine (beta-ala) as a precursor is constructed by heterologous expression of aminotransferase and malonyl-CoA reductase: firstly, under the catalysis of transaminase, amino of beta-ala is transferred to alpha-keto acid (such as pyruvic acid, oxaloacetic acid or alpha-ketoglutaric acid and the like), and then the malonyl-CoA is obtained; an intermediate product 3-oxopropionic acid and corresponding amino acid are formed; and the malonyl-CoA is generated from the 3-oxopropionic acid under the action of the malonyl-CoA reductase. According to the method, the defects existing in a natural malonyl-CoA synthesis route, such as low carbon utilization rate, energy substance ATP consumption, greenhouse gas CO2 release, pyruvate dehydrogenase (PDH) of route enzymes and acetyl-CoA carboxylase (ACC) which are strictly regulated and controlled, are overcome, and high yield of products taking malonyl-CoA as a precursor, including light flavomycin, octanoic acid, phloroglucinol, pentadecheptaene, natamycin, spinosad and the like, is realized.

The invention belongs to the technical field of leaf surface resistance and control agents, and particularly relates to a leaf surface resistance and control agent for reducing the content of cadmium and lead in rice and a preparation method thereof. The invention relates to a leaf surface blocking and controlling agent, which is prepared by mixing the following components in percentage by mass: 3 to 15 percent of active component, 6 to 15 percent of dispersing agent and the balance of inorganic salt, the active component is formed by compounding ethylenediaminetetraacetic acid, oxaloacetic acid and silicon dioxide sol. The foliar blocking and controlling agent disclosed by the invention takes ethylenediaminetetraacetic acid, oxaloacetic acid and silicon dioxide as active ingredients, so that accumulation of heavy metals cadmium and lead in rice can be remarkably reduced, further the content of cadmium and lead in rice can be effectively reduced, and a support is provided for safe production of rice. Besides, positive ions in inorganic salts such as zinc sulfate, manganese sulfate and ferrous sulfate can antagonize transfer of cadmium and lead in rice plants to the rice, so that accumulation of heavy metal cadmium and lead in the rice is reduced, elements such as zinc, manganese and iron required by growth of the rice can be supplemented, and growth of the rice plants is promoted.

The present application relates to the field of polymerized rosin, more specifically, it relates to a zinc-free polymerized rosin and a preparation method thereof. A zinc-free polymerized rosin comprises the following raw materials: masson rosin, inorganic acid, zinc chloride, solvent, oxaloacetic acid, and phosphotungstic acid; the inorganic acid is 0.6-1% of the mass of masson rosin, the zinc chloride is 2.5-4.5% of the mass of masson rosin, the solvent is 75-85% of the mass of masson rosin, the oxaloacetic acid is 0.04-0.08% of the mass of masson rosin, and the phosphotungstic acid is 0.04-0.08% of the mass of masson rosin. The zinc-free polymerized rosin provided in this application can not only maintain a high yield of the product, but also thoroughly remove zinc residues, which helps to break the foreign technology monopoly, enhance the overall competitiveness of the domestic ink industry, and contribute to the healthy development of the national economy.

The invention discloses a construction method and application of engineering bacteria for improving carbon flow supply in L-malic acid production, and belongs to the technical field of biological engineering. A construction method of the engineering bacteria comprises the following steps: amplifying malate dehydrogenase genes mdh1, mdh2 and mdh3 from a genome of saccharomyces cerevisiae, constructing double-gene combined expression recombinant plasmids, and respectively introducing the recombinant plasmids into host bacteria to obtain the engineering bacteria mdh1, 2, mdh1, 3 and mdh2, 3. The yield of accumulated L-malic acid is increased by 13-16 times compared with the yield of the L-malic acid accumulated by the engineering bacteria containing double-gene combined expression, which is constructed by the method disclosed by the invention, compared with the yield of the L-malic acid accumulated by an original strain. According to the engineering bacterium construction method for improving carbon flow supply in L-malic acid production, the capacity of converting oxaloacetic acid into malic acid is improved, carbon flow supply is increased, then the yield of L-malic acid is increased, and good industrial application value and prospects are achieved.

The invention belongs to the technical field of leaf surface resistance and control agents, and particularly relates to a leaf surface resistance and control agent for reducing the cadmium content of rice and a preparation method thereof. The leaf surface blocking and controlling agent for reducing the cadmium content of the rice is formed by compounding active ingredients of oligosaccharide and oxaloacetic acid, and the mass ratio of the oligosaccharide to the oxaloacetic acid is (1-100): (100-1). Chitosan oligosaccharide and oxaloacetic acid are mixed to serve as an active component of the leaf surface blocking and controlling agent, and rice tests find that when the active component is sprayed on leaf surfaces of rice in the booting stage and the filling stage respectively, transportation and accumulation of heavy metal cadmium in soil in the rice can be effectively prevented and controlled, and then the content of the heavy metal cadmium in the rice can be reduced; and support can be provided for green and safe production of rice. In addition, positive ions in inorganic salts such as zinc sulfate, manganese sulfate and ferrous sulfate can antagonize transfer of cadmium and lead in rice plants to the rice, so that accumulation of heavy metal cadmium and lead in the rice is reduced, elements such as zinc, manganese and iron required by growth of the rice can be supplemented, and growth of the rice plants is promoted.

This invention discloses a culture medium and process for alleviating ammonium accumulation in cells. The concentrations of the substances added to the culture medium are as follows: 2 g / L glutamate, 0 g / L glutamine, 2 g / L aspartic acid, 2 g / L asparagine, 1 g / L serine, 1 g / L pyruvate, 0.5 g / L α-ketoglutarate, 0.5 g / L oxaloacetic acid, 0.5 g / L proline, 0 g / L glucose, 8 g / L galactose, and 0.1% glycerol. Compared with the prior art, the advantages of this application are: this method mainly achieves the purpose of maintaining cell viability and reducing the cell metabolic byproduct ammonium ions by adjusting the proportion of substances related to cell metabolic pathways and adding additional cell protectants; using the optimized culture medium of this invention, the cell viability can be increased from 42.38% to 95.21% and the ammonium ion concentration can be reduced from 6.308 mM to 0.914 mM by day 7.

The invention belongs to the field of synthetic biology, and particularly relates to a genetically engineered bacterium for high-yield non-protein amino acid as well as a construction method and application of the genetically engineered bacterium. The genetically engineered bacterium is obtained by taking Escherichia coli HSCC4 as an original strain and carrying out the following various series of metabolic engineering modifications on the original strain, including a way of reducing the consumption of malic acid to generate pyruvic acid; the carbon flow is limited to enter a complete TCA cycle for oxygenolysis, and carbon metabolism is forced to more depend on a supplementation pathway to generate oxaloacetic acid; and the competitive pathway of carbon and nitrogen flowing to branched chain amino acid synthesis is reduced. The original strain is subjected to specific metabolic engineering modification, so that the original strain can better utilize carbon source substances such as glucose and the like to produce the L-homoserine, nutritional defects are remarkably reduced, and the strain without plasmids has better production performance. Compared with a starting strain HSCC4, the genetically engineered strain disclosed by the invention has the advantages that the shake flask level of a plasmid-free strain is improved from 18.83 g / L to 20.25 g / L, and the genetically engineered strain has important industrial application value.

The invention belongs to the technical field of biology, and discloses a biosynthesis method of 2, 4-dihydroxybutyric acid. According to the biosynthesis method, L-malic acid and formaldehyde serve as substrates to synthesize 2, 4-dihydroxybutyric acid, L-malic acid is converted into oxaloacetic acid through L-malic dehydrogenase, oxaloacetic acid is decarboxylated to generate pyruvic acid, pyruvic acid and formaldehyde are condensed under the action of aldolase to generate 2-ketone-4-hydroxybutyric acid, and 2, 4-dihydroxybutyric acid is converted into 2, 4-dihydroxybutyric acid through dehydrogenase. The invention relates to 2, 4-dihydroxybutyric acid. The method can be realized through an in-vitro multi-enzyme catalysis system, and can also be completed by introducing a way into microorganisms. Furthermore, the formaldehyde can be generated from methanol, formic acid or sarcosine under the action of enzyme. Therefore, the monocarbon resources such as methanol and formaldehyde can be introduced to synthesize the 2, 4-dihydroxybutyric acid with high value, the raw materials are low in price, and the whole synthesis method has the advantages of high atom utilization rate and high conversion rate.

The invention discloses a construction method and application of an engineering bacterium for increasing the yield of alpha-ketoglutaric acid. Wild E.coli.W3110 serves as a chassis strain, lactic dehydrogenase ldhA, pyruvate dehydrogenase poxB and formic acid C-acetyltransferase pflB are knocked out firstly, and the flow direction of pyruvic acid to lactic acid, acetic acid and formic acid is blocked; meanwhile, the promoter PBBaJ23109 is used for replacing a natural promoter of the sucA gene, so that alpha-ketoglutaric acid dehydrogenase is weakened, and the decomposition way of alpha-ketoglutaric acid is weakened; the phosphoenolpyruvate carboxylase ppc is overexpressed, and the flow direction of phosphoenolpyruvate to oxaloacetic acid is enhanced; isocitrate dehydrogenase icd from escherichia coli is overexpressed, so that synthesis of a product is promoted; besides, pyruvate dehydrogenase derived from saccharomyces cerevisiae is introduced and coded by genes PDB1, PDA1 and LAT1, so that an important precursor, namely pyruvic acid, is promoted to flow to acetyl coenzyme A; the engineering strain with high yield of alpha-ketoglutaric acid is finally obtained, the yield of 75.1 g / L can be achieved in a 5L fermentation tank through a fed-batch fermentation method for 40 hours, and the conversion rate is 39.6%.

The application discloses a construction method and application of recombinant bacteria for efficiently converting glucose to produce tetrahydropyrimidine, and the recombinant bacteria are constructed according to a biosynthesis pathway of tetrahydropyrimidine and a carbon metabolic flow distribution of balanced phosphoenolpyruvic acid to oxaloacetic acid and pyruvic acid, and the recombinant bacteria strain directly produces tetrahydropyrimidine by fermentation with glucose as a substrate; 36-53 g / L of tetrahydropyrimidine can be accumulated in a 56-hour fermentation liquor, the yield per cell reaches 1.21-1.91 g / g DCW, and the glucose molar conversion rate reaches 0.31-0.38 mol / mol, and the yield, the yield and the conversion rate are all higher than those of an existing process; compared with an existing fermentation method and a whole-cell catalysis method for producing tetrahydropyrimidine salt, the recombinant bacteria provided by the application have the advantages of low raw material cost, simple culture condition, small equipment loss, short fermentation period, simple operation, no need to collect bacterial bodies to extract enzyme liquor and high tetrahydropyrimidine production efficiency.

The invention relates to methods for treating symptoms of PMS and PMDD including muscle ache, bloating, cramping, acne, tender breasts, bloating, fatigue, difficulty concentrating, diminished impulse control, irritability, anxiety, tension, anger, depression, insomnia and / or rapid fluctuations in mood (mood swings). The method comprises administration of a pharmaceutical composition comprising oxaloacetate, oxaloacetate salts, oxaloacetic acid and / or anhydrous enol-oxaloacetate.

Method and compositions for producing malonyl-CoA and / or triacetic acid lactone within peroxisomes using genetically modified yeast cells to metabolize a substrate containing fatty acids, vegetable oil, or alkanes, and genetically modified organisms are provided. Also provided are methods to generate acetyl-CoA, which is retained in the peroxisomes due to genetic modifications that prevent its export therefrom. A modified enzyme with a peroxisomal targeting sequence catalyzes a reaction between acetyl-CoA and oxaloacetate, producing pyruvate and malonyl-CoA. The methods can include deleting carnitine acetyltransferase (CAT2) alleles to prevent acetyl-CoA export from peroxisomes, and using genes encoding methylmalonyl-CoA carboxyltransferase subunits with peroxisomal targeting sequences. Additionally, the method incorporates 2-pyrone synthase genes to further facilitate production processes.

The present invention relates to a fig grafting and cultivation method, and relates to the technical field of fig planting. The fig grafting and cultivation method includes selecting and treating a rootstock, selecting and treating a scion, a first grafting and cultivation, and a second grafting and cultivation. The rootstock selection and treatment step includes soaking the root of the rootstock in a first treatment agent for a first soaking treatment. The first treatment agent comprises 200-350 g of oxaloacetic acid, 1-5 g of gibberellin, and 50-60 g of carbendazim per 1000 L of water. The scion collection and treatment step includes soaking the scion in a second treatment agent for a second soaking treatment. The second treatment agent comprises 2-5 g of oxaloacetic acid per 500 mL of water. The present invention significantly improves the grafting survival rate and fig yield by introducing oxaloacetic acid to soak the rootstock and scion during fig grafting and cultivation, thus overcoming the shortcomings of the prior art.

Disclosed is a novel genetically modified microorganism showing improved yields of 3-hydroxyadipic acid and / or α-hydromuconic acid. The genetically modified microorganism is a microorganism having an ability to produce 3-hydroxyadipic acid and / or α-hydromuconic acid, in which the reaction to generate malic acid from oxaloacetic acid is enhanced, and the reaction to generate acetyl-CoA from pyruvic acid is enhanced. In addition, the reaction to generate carbon dioxide from formic acid is enhanced.

The invention provides a phosphoenolpyruvate carboxylase mutant. Compared with wild phosphoenolpyruvate carboxylase as shown in SEQ ID NO.1, the amino acid sequence of the mutant is subjected to single-point mutation or combined mutation on amino acids at the 424th site, the 513th site, the 683th site, the 800th site and the 886th site. Compared with a wild enzyme, the phosphoenolpyruvate carboxylase mutant provided by the invention has the advantages that the thermal stability and the production rate of oxaloacetic acid prepared by carbon sequestration are greatly improved, and the phosphoenolpyruvate carboxylase mutant has a good industrial application prospect.

A genetically modified microorganism which satisfies at least one condition selected from the group consisting of the following conditions (I) and (II). Condition (I): citrate synthase activity is reduced or inactivated compared with a wild-type microorganism corresponding to the genetically modified microorganism, and condition (II): oxaloacetate decarboxylase activity is reduced or inactivated compared with the wild-type microorganism.

The invention discloses a construction method of a photosynthetic engineering bacterium for producing succinic acid by using industrial waste gas CO. The construction method comprises the following specific steps: 1, selecting a chassis strain, namely selecting synechocystis PCC6803 or synechocystis PCC7942 containing Rubisco gene clusters as the chassis strain; step 2, strengthening a COfixed module: strengthening the Rubisco enzyme activity, accelerating COhydration by overexpressing carbonic anhydrase, and constructing carboxylates to improve the local concentration of CO2; and 3, reinforcing a succinic acid synthesis module: introducing heterologous phosphoenolpyruvate carboxylase from escherichia coli and malate dehydrogenase from saccharomyces cerevisiae, carboxylating the phosphoenolpyruvate carboxylase into oxaloacetic acid, and reducing the oxaloacetic acid into malic acid. The photosynthetic engineering bacteria are constructed, a COconcentration mechanism and a succinic acid synthesis route are integrated, the concentration of succinic acid within 72 hours reaches 12.3 g / L, the COfixing amount is 22.1 g / L, and the yield is increased by 200% compared with that of a wild strain.

The application provides a CO2 capture method and a CO2 capture device coupled with electrochemical regeneration of hydrogen. The method comprises the following steps: absorbing CO2 in a CO2-containing gas by using an alkaline solution to form a CO2-rich solution; performing acid-base neutralization of the CO2-rich solution and an acidic solution to obtain a neutralization solution and CO2; performing electrolysis of the neutralization solution to obtain a cathode electrolysis product and an anode electrolysis product, wherein the cathode electrolysis product is H2 and the alkaline solution, and the anode electrolysis product is O2 and the acidic solution; and the acidic solution is selected from one or a combination of more than two of the following solutions: pyruvic acid solution, gluconic acid solution, malonic acid solution, tartaric acid solution, glyceric acid solution, oxalacetic acid solution, formic acid solution, isopropionic acid solution, isobutyric acid solution, fumaric acid solution, aconitic acid solution, isocitric acid solution and hexanediol diacid solution. The acidic solution generated by electrolysis can avoid corrosion of the device equipment and reduce the net energy consumption and net cost of the CO2 capture process.

The application discloses a high-yield beta-alanine engineering bacterium and method based on a type I CRISPRi screening system, wherein by knocking out a pckA gene encoding oxaloacetate to phosphoenolpyruvate and a nadB gene encoding L-aspartate to oxaloacetate, a countercurrent pathway for synthesizing beta-alanine is blocked, and carbon flow loss is reduced; by knocking out an ldhA gene and a poxB gene, the content of synthesized pyruvate is increased; by overexpressing an NCgl0580 gene, the tolerance of EcN to products is improved; by knocking out a lacI gene in a genome, the adding cost of an inducing agent in a fermentation process is reduced; by optimizing a type I CRISPRi system for high-throughput screening of target genes affecting the yield of beta-alanine in the engineering bacterium, the screening efficiency and accuracy are significantly improved, an aspartate tRNA ligase gene aspS capable of improving the yield of beta-alanine is obtained, by overexpressing the aspS, the PanD enzyme activity is increased, and the yield of beta-alanine is further improved.

The invention relates to methods for treating symptoms of PMS and PMDD including muscle ache, bloating, cramping, acne, tender breasts, bloating, fatigue, difficulty concentrating, diminished impulse control, irritability, anxiety, tension, anger, depression, insomnia and / or rapid fluctuations in mood (mood swings). The method comprises administration of a pharmaceutical composition comprising oxaloacetate, oxaloacetate salts, oxaloacetic acid and / or anhydrous enol-oxaloacetate.

The invention provides a synthesis method of 4, 7-dichloroquinoline, and relates to the technical field of compound preparation. Comprising the following steps: synthesizing 7-chloro-4-hydroxyquinoline-2-carboxylic acid by a one-pot method, and then carrying out decarboxylation and chlorination on the 7-chloro-4-hydroxyquinoline-2-carboxylic acid to obtain the 4, 7-dichloroquinoline. Wherein the step of synthesizing the 7-chloro-4-hydroxyquinoline-2-carboxylic acid by the one-pot method comprises the following steps: condensing m-chloroaniline and diethyl oxaloacetate to obtain a compound shown as a formula 3, directly adding condensation reaction liquid into an organic solvent, and heating and cyclizing to obtain 7-chloro-4-hydroxyquinoline-2-carboxylic acid ethyl ester; after the cyclization reaction is completed, sodium hydroxide is added for hydrolysis, and 7-chloro-4-hydroxyquinoline-2-carboxylic acid is obtained. The method has the advantages of simple operation, high productivity, safety, environmental protection, easily available raw materials, and suitableness for industrial production.

The invention provides an excellent gene THP3 capable of increasing the corn protein content, the THP3 encodes mutant glutamate oxaloacetic acid transaminase (GOT1), the THP3 gene can be used for constructing grain and whole-plant high-protein corn, and the variation site of the THP3 gene can be used for genetic improvement of the high-protein corn. In addition, THP3 and THP9 are introduced into the corn at the same time, and the protein content of the corn kernels and the whole plant can be further increased.

The present disclosure provides plants that express a variant phosphoenolpyruvate carboxylase (PEPC) enzyme. The plants have enhanced resistance to aluminum than comparable plants that lack the variant PEPC enzyme. In addition, the plants more effectively sequester carbon, extract phosphate, and produce oxaloacetate-derived amino acids and glucose than comparable plants that lack the variant PEPC enzyme. The disclosure also provides tools for production of plants that express the variant PEPC enzyme.

Described herein is a novel enzymatic pathway and acid tolerant Schizosaccharomyces pombe strain exhibiting the same, for producing 3-hydroxypropionic acid by fermentation wherein the S. pombe strain includes nucleotide sequences that encode, and which are operably linked to promoters to express, non-native enzymes that exhibit an oxaloacetate decarboxylase (ODC) activity that converts oxaloacetate to 3-oxopropionate and a 3-oxopropionate reductase (OPR) activity that converts the 3-opropionate to 3-hydroxypropianate. ODC and OPR enzymes are not known to exist in nature, nor is an enzymatic path for making 3-hydroxypropionic acid but particular enzymes exhibiting the requisite activities are herein identified by sequence. A further enhancement is to also overexpress an enzyme that has at least one of a pyruvate carboxylase activity, a phosphoenolpyruvate carboxy kinase activity, and a phosphoenolpyruvate carboxylase activity, which increases the level of oxaloacetate in the cell leading to greater 3-HP production.

The present invention provides non-natural microorganisms containing enzymatic pathway and / or metabolic modifications for increasing carbon flux by acetyl-CoA or by oxaloacetic acid and acetyl-CoA. Embodiments of the invention include a microorganism having a pathway for obtaining acetyl-CoA and oxaloacetic acid (PK pathway) comprising a phosphoketolase. The microorganism also has (i) a genetic modification that enhances the sugar uptake activity of a non-phosphotransferase (non-PTS) system, and / or (ii) a genetic modification in the electron transport chain (ETC) of the microorganism that increases the efficiency of ATP production that increases the availability of reducing equivalents, or both. The microorganism may optionally include (iii) a genetic modification that maintains, attenuates, or eliminates the sugar uptake activity of a phosphotransferase system (PTS). The increased carbon flux by acetyl-CoA and oxaloacetic acid may be used for the production of biologically derived compounds, and the microorganisms may further include pathways capable of producing biologically derived compounds.