519 results about "Histidine" patented technology

The invention discloses a diluent for whole blood lateral immunochromatography detection as well as a preparation method and a detection method thereof, and belongs to the technical field of immunochromatography detection. The diluent solves the technical problems of unsmooth chromatography, background interference, poor stability of detection results and the like caused by red blood cells during direct detection of whole blood samples. The diluent comprises a buffer system, an osmotic pressure regulator glycine, a nonionic surfactant polysorbate, an erythrocyte aggregation inducer polyvinylpyrrolidone, a dynamic viscosity regulator trehalose, a blocking protein, a stabilizer combination L-methionine and L-histidine, and a composite formula of water. Red blood cells are effectively induced to gather and intercept on the sample pad through the synergistic effect of all the components, and meanwhile the stability of the chromatography process and the activity of the detection reagent are maintained. The diluent is mainly used for lateral immunochromatography quantitative detection of markers such as pro-enkephalin, C-reactive protein, cardiac troponin I or N-terminal pro-brain natriuretic peptide in a whole blood sample.

The invention belongs to the technical field of immunodetection, and discloses a kit for detecting the ratio of proBDNF to maure BDNF based on structural dynamics guidance and a preparation method of the kit, the kit comprises a solid phase carrier and a detection reagent, the three antibodies are determined on the basis of full-length conformational kinetics analysis of brain-derived neurotrophic factors; the first capture antibody targets an innate disorder region (SEQ ID NO: 1) of a proBDNF propeptide region; the second capture antibody targets an innate disorder region (SEQ ID NO: 2) of a proBDNF propeptide region; the second capture antibody is a neo-epitope specific antibody, is specifically combined with an N terminal (SEQ ID NO: 2) exposed by maure BDNF enzyme digestion, and is combined with a free alpha-amino group strictly dependent on the first histidine; and the universal detection antibody is combined to a Loop 4 region (SEQ ID NO: 3) of the Mature structural domain. The problems of steric hindrance and cross reaction in traditional immunodetection are solved through a structural biology strategy, and accurate distinguishing and ratio quantification of proBDNF and maure BDNF are achieved.

The invention discloses a preparation method of an edible pectin film capable of monitoring and prolonging fruit freshness, which comprises the following steps: carrying out oxidation reaction on pectin and sodium periodate, then terminating the reaction and purifying to obtain oxidized pectin; the preparation method comprises the following steps: dissolving oxidized pectin in water, then adding histidine, and carrying out heating reaction at 60-120 DEG C for 1-3 hours to obtain a reaction product with pH-responsive fluorescence characteristics; adding a calcium chloride aqueous solution as a cross-linking agent into the reaction product, simultaneously adding glycerol as a plasticizer, stirring and mixing for 5-15 minutes at the temperature of 50-70 DEG C, and then stirring and mixing for 1.5-2.5 hours at the temperature of 20-30 DEG C to obtain a uniform film forming solution; pouring the film-forming liquid into a film, and drying to obtain an edible pectin film; the invention also provides the edible pectin film prepared by the preparation method. The prepared edible pectin film is mainly used for packaging fruits, and the freshness of the fruits can be visually displayed through fluorescence change while the fruits are kept fresh.

The invention discloses a preparation method of a metal doped type hydroxyapatite nanoflower. The method specifically comprises the following steps: dispersing a calcium source and soluble metal salt into water, adding acid phosphate, urea and L-histidine, uniformly mixing, carrying out a hydrothermal reaction, mechanically stirring, filtering, washing, and drying a hydrothermal system precipitate to obtain the corresponding metal-doped hydroxyapatite nanoflower. Compared with the prior art, the metal-doped hydroxyapatite nanoflower prepared by the preparation method disclosed by the invention is directly assembled by nanosheets, and a single metal type can be doped in a customized manner. According to the method, water is used as a unique solvent, the use of an organic solvent is avoided, the pH does not need to be adjusted in advance, the technological process is simple, operation is convenient, equipment investment is small, and the method is suitable for industrial production.

There is provided a method for diagnosing a subject with early onset muscle atrophy, said method comprising: obtaining a biosample from the subject; and assaying the biosample for one or more biomarkers, said one more biomarkers are taurine, proline, citrulline, trigonelline, thymidine, ornithine, glutamate, L-pyroglutamic acid, creatinine, adenine, nicotinamide, 2-methylhippuric acid, maltol, L-arginine, hypotaurine, L-glutamine, homogentisic acid, methylhistidine, oxoglutaric acid, xanthine, L-carnitine, succinate, or a combination thereof; and identifying the subject with early onset muscle atrophy on the basis of a deviation in the one or more of said one more biomarkers.

A major challenge in the field of antibody-based therapeutics is the development of antibodies that have longer duration of action, longer half-life and can be delivered to a patient at lower doses. The current methods to achieve this aim depend on the engineering modification of the pH-dependent antigen binding properties of the antibodies, which is very strenuous and generally requires further optimization of the pH-sensitive interactions in a low-throughput, individualized manner because these methods depend mainly on the introduction of histidine mutations in specific antibody complementarity determining regions (CDRs). In the present invention, the inventors provide antibodies and other antigen-binding proteins that carry mutations outside of the complementals, thereby conferring universal pH-sensitive binding properties to the antibodies. The invention also relates to methods of isolating and generating said antigen binding proteins, compositions and medical uses thereof.

The invention discloses application of copper-amino acid nano enzyme in preparation of anti-inflammatory drugs, and relates to the technical field of biomedical new materials, amino acids comprise glycine, arginine, histidine, threonine, phenylalanine and cysteine; the ratio of the amino acid to the copper ions is 1: (0.5-5), and the synthesis temperature of the copper-cysteine nano enzyme is 25-125 DEG C. The copper-amino acid nano-enzyme library established by the invention has efficient hydroxyl free radical, superoxide free radical and hydrogen peroxide scavenging activity; wherein the copper-cysteine nano-enzyme shows the highest enzymatic activity, and shows low toxicity and good biocompatibility in both the cell level and the animal level; meanwhile, the copper-cysteine nano-enzyme also shows anti-inflammatory activity and anti-oxidative stress activity, can remarkably improve cell inflammation and body inflammation, relieves and treats dextran sodium sulfate induced mouse ulcerative colitis, and can be further applied to preparation of drugs for treating inflammatory bowel diseases.

The present application provides: a microorganism with enhanced lipoate protein ligase activity; a composition for producing histidine comprising the microorganism; and a method for producing histidine, the method comprising a step for culturing the microorganism.

The invention discloses an amino absorbent for promoting CO2 desorption and application of the amino absorbent, and belongs to the technical field of CO2 trapping. The amino absorbent comprises histidine and an amine absorption liquid, and the histidine serving as a catalyst is dissolved in the amine absorption liquid to prepare the amino absorbent for promoting CO2 desorption. The histidine provided by the invention is used as a catalyst for catalyzing CO2 desorption. Experiments show that by adding a small amount of histidine (such as 0.22 wt%), the desorption amount and the maximum desorption rate of CO2 can be remarkably improved, the maximum desorption rate can be improved to 34.0%, and regeneration heat consumption is reduced to 71.7% of the standard. The histidine realizes high-efficiency and low-energy-consumption CO2 desorption by changing a reaction path, inhibiting generation of stable carbamate and promoting proton transfer and amine regeneration, and the catalyst has good stability and can be recycled. And the histidine serving as the catalyst has the characteristics of homogeneous phase and dissolved state, so that the engineering application problem of a solid catalyst in a liquid phase reaction system is fundamentally solved.

The invention discloses an ergothioneine-producing recombinant engineering bacterium as well as a construction method and application thereof, and belongs to the technical field of gene recombination fermentation. The method comprises the following steps: by taking escherichia coli as a starting bacterium, carrying out recombinant expression on a histidine trimethyl inner salt cysteine sulfoxide synthetase egt1 gene, an L-histidine methyltransferase egtD gene, a histidine trimethyl inner salt cysteine sulfoxide lyase egt2 gene, a methionine adenosine transferase metK gene, an adenylate kinase adK gene and an adenine phosphoribose transferase apt gene; on this basis, supply of precursor substances including histidine, cysteine and methionine is further improved through metabolic transformation, the yield of the finally obtained recombinant engineering bacterium for producing ergothioneine reaches 2.54 g / L after 48 h of shake-flask culture, the yield of a 5L fermentation tank reaches 18 g / L after further enlarged culture, the yield of ergothioneine is guaranteed while energy consumption and cost are reduced, and the method is suitable for industrial production. The method is suitable for practical popularization.

The invention provides a composite hydrogel for promoting diabetic bone regeneration, the composite hydrogel is composed of L-histidine modified chitosan, oxidized konjac glucomannan, Zn and nano clay, and in-situ gelation is realized through coordination regulation, interlayer exchange and dynamic covalent bond synergistic effect. Through combined application of coordination regulation, interlayer exchange and dynamic covalent bonds, on-demand staged delivery of various ions is realized. According to the innovative design, the adhesive property and mechanical integrity of the hydrogel at a defect part are maintained, intelligent response can be realized according to the change of a bone microenvironment, and the defect that a single release mechanism in the prior art is difficult to meet the complicated demand of diabetic bone regeneration is overcome.

An Fc-binding polypeptide with improved alkaline stability comprising a mutant of the Fc-binding domain of Staphylococcus protein A (SpA), said mutant being defined by SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, SEQ ID NO: 5, SEQ ID NO: 6, SEQ ID NO: 7, SEQ ID NO: 22, SEQ ID NO 51 or EQ ID NO 52, wherein at least the asparagine or serine residue at a position corresponding to position 11 in SEQ ID NO: 4-7 has been mutated to an amino acid selected from the group consisting of glutamic acid, lysine, tyrosine, threonine, phenylalanine, leucine, isoleucine, tryptophan, methionine, valine, alanine, histidine and arginine.

The invention discloses construction and application of a Primrose syndrome non-human animal model, and belongs to the technical field of animal models and disease research. According to the invention, through a CRISPR / Cas9 technology, a codon CAC for coding 596th histidine in a No.14 exon of a mouse Zbtb20 gene is subjected to site-directed mutagenesis into CGC for coding arginine, and a hybrid mouse model for simulating pathogenic point mutation (p.H596R) of human Primrose syndrome is constructed. The model can stably reproduce key clinical phenotypes of the Primrose syndrome, including overgrowth after adult, serum IGF-1 rise, memory dysfunction and anxiety behaviors, and shows abnormal hippocampal neuronal development and synaptic transfer related pathways and the like. The invention provides an important experimental tool for deeply revealing the pathological mechanism of Primrose syndrome, developing drug screening and treatment intervention research and the like.

The present invention provides a composition comprising collagenase as an enzyme; calcium, histidine, and glycine as coenzymes, and a method for stabilizing enzymes, the method comprising the preparation of the composition by adding histidine and glycine to collagenase. According to the present invention, the enzyme composition and method for stabilizing enzymes can minimize or inhibit the agglutination of enzymes, maintain the concentration of freeze-dried enzymes even during long-term storage, and provide a formulation that has excellent rehydration time and hygroscopicity when restored to a liquid state, as well as superior enzyme activity.

The present application relates to the field of external ointment preparation, and provides a zinc gluconate ointment and a preparation method thereof.The ointment comprises, by mass fraction: 0.3-2.0 parts of zinc gluconate, 0.05-1.5 parts of L-histidine, 0.05-1.0 parts of polysaccharide, and the balance of purified water, wherein the polysaccharide is chitosan oligosaccharide or hyaluronic acid oligomer.The zinc gluconate, L-histidine and polysaccharide are dispersed to form hydrogel microdroplets under the condition of pH 5.0-6.0, and are further dispersed in the continuous phase of the oil phase.By establishing a complex system in a weak acid environment and using a double constraint structure of microdroplet dispersion and oil phase, the free Zn 2+ The initial release rate is reduced, skin irritation caused by the initial release of traditional preparations is avoided, and a high 24-hour cumulative release amount is maintained.The ointment exhibits excellent physical stability and particle size uniformity during storage, avoids oil-water layering and crystallization, and has both sustained release and good use feeling.

The application provides a betahistine lyophilized powder and a preparation method thereof. The betahistine lyophilized powder comprises drug-loaded microcapsules and a lyophilized matrix. The drug-loaded microcapsules and the lyophilized matrix are dissolved in water to form a lyophilized solution for lyophilization. The drug-loaded microcapsules are formed by coating betahistine raw materials with pH-sensitive polymer layers and nanometer particles of citric acid. The lyophilized matrix comprises histidine, citrate and a lyophilized skeleton agent. The histidine and citrate in the lyophilized matrix maintain the overall pH stability (3.5-4.5) during the storage period, preventing pH drift. If the moisture invades during the storage period and the pH rises to 5.0 or above, the pH-sensitive polymer layer dissolves, and the internal nanometer particles of citric acid further adjust the pH value as an emergency buffer. Through the synergistic effect of the endogenous emergency buffer microcapsules and the exogenous active buffer matrix, the pH stability requirement during the storage period is covered.

The application provides an arginine mutant and application thereof in 1,4-butanediamine biosynthesis, and belongs to the field of bioengineering. Escherichia coli The mutant is obtained by site-directed mutagenesis of key site amino acid residues based on wild-type EcAdiA from strain The application improves the enzyme activity stability of arginine decarboxylase in neutral environment, improves the conversion rate and conversion speed of 1,4-butanediamine in neutral environment, and lays a foundation for high-efficiency biosynthesis of 1,4-butanediamine.

The invention discloses a generalized pustular psoriasis diagnosis marker based on metabonomics and application of the generalized pustular psoriasis diagnosis marker. The diagnostic marker is prepared from one or more of the following 35 compounds: pyruvic acid, alpha-ketoisovaleric acid, 2-hydroxybutyric acid, 3-hydroxybutyric acid, methane thiophosphoric acid, proline, uracil, tranexamic acid, 4-aminobutyric acid, threonine, scopoletin, dodecanol, N-methyl-L-leucine, L-cysteine-glycine and L-kynurenine. The feed additive is prepared from the following raw materials: 3-hydroxybenzoic acid, allantoin, delta-tocopherol, xylofuranose, glucose-1-phosphoric acid, pyrophosphate, taurine, L-asparagine, phthalic acid, 4-(dimethylamino) azobenzene, 5-tert-butyl-1h-indole-2, 3-dione, quinic acid, glucose, histidine, lysine, palmitic acid, 7-methylguanine, oleic acid and whale acid. The marker can be used for accurately distinguishing patients with generalized pustular psoriasis from healthy people.

The invention relates to a double-layer colorimetric sensing array for visually monitoring freshness of meat products in real time and a preparation method and application thereof, and belongs to the technical field of food nondestructive testing. The preparation method of the double-layer colorimetric sensor array for real-time visual monitoring of the freshness of the meat product comprises the following steps: adding carboxymethyl cellulose into water for dissolving, and adding anthocyanin to prepare an anthocyanin solution; then mixing the anthocyanin solution with the deep eutectic solvents with different concentrations, uniformly stirring to obtain a mixed solution, standing, defoaming and drying to obtain a colorimetric sensing array indicating layer; the deep eutectic solvent is prepared from choline chloride and histidine; and carrying out electrostatic spinning on the upper surface of the colorimetric sensing array indication layer by adopting an electrostatic spinning mode to obtain the double-layer colorimetric sensing array. The sensor has excellent stability and sensitivity under a high-humidity condition, and also has the advantages of good reusability, portability, visualization, no damage, biodegradability and the like.

This invention relates to the field of automatic control technology, specifically to a method for stabilizing and controlling the effective chlorine content of sodium hypochlorite solution. During the cooling stage of the sodium hypochlorite solution, an online electrochemical sensor acquires the concentration signal of free trace metal ions in the solution. When the signal reaches a preset threshold of the controller, the controller instructs a peristaltic pump to add a compound stabilizer to the solution. The compound stabilizer is prepared by mixing a specific short peptide containing cysteine ​​and histidine with a silicate buffer solution. After adding the compound stabilizer, the solution undergoes short-term ultrasonic cavitation treatment. This method uses a specific short peptide instead of traditional aminopolycarboxylate salts, avoiding the breaking and failure of carbon-nitrogen bonds under strong oxidizing conditions, preventing secondary release of metal ions that could trigger catalytic decomposition, extending the effective chlorine half-life, and reducing the amount of chlorate byproducts generated.

A method for high-density fermentation production of ULP involves culturing yeast containing a ULP expression vector in a basal medium comprising a carbon source (glycerol) and a nitrogen source (histidine and / or ammonium dihydrogen phosphate). This invention, through high-density yeast fermentation and employing an improved culture medium and process, significantly improves the yield and quality of ULP. The final expression level is 3-5 times higher than that achieved by conventional E. coli fermentation methods, reducing ULP production costs by at least 25%. This reduces the cost of related recombinant protein drugs and allows for wider application of this high-quality system in recombinant protein drug development.

The present invention relates to a cosmetic composition, advantageously an eco-biological cosmetic composition, comprising: - polyglutamic acid or a salt thereof; and - at least one peptide derivative represented by the general formula (I) in which: - R1 represents a hydrogen atom, an acyl radical or an acyloxy radical; and - R2 represents the side chain of an alpha-amino acid chosen from the group consisting of phenylalanine, glutamic acid, arginine, cysteine, methionine, histidine and tyrosine. The present invention also relates to the use of said cosmetic composition for combating skin redness and / or skin aging; to its use for preventing and / or combating cutaneous vascular hyperproliferation and / or cutaneous inflammation and / or rosacea; and to a method for selecting compounds suitable for preventing and / or combating these pathologies.

Described is a compound for substituting amino acids of proteins or peptides, wherein the compound has the formula (1)wherein the stereocenter C1* represents CH that either results in the D- or L-form of the compound of formula (1); A− is a negatively charged ion compensating the positive charge; X1 is H or an amine protecting group; X2 is OH, an ester residue or an amide residue or an activated carboxylic acid derivate to be used for the formation of an amide bond; Y1, Y2 and Y3 are independently from each other a C1-C6 alkyl, and Z1 and Z2 are independently from each other a nucleobase, a C1 to C16 alkyl group, an aromatic residue or a heteroaromatic residue, wherein the aromatic residue or the heteroaromatic residue contains one 5, 6, or 7-membered ring or two condensed 5, 6, or 7-membered rings sharing two carbon atoms, wherein the aromatic residue or the heteroaromatic residue can be substituted by a linear or branched C1 to C16 alkyl group and / or a further aromatic group. Furthermore, a method for preparing this compound and proteins and peptides containing this compound are disclosed.

The application discloses a fabric yellowing reagent and a fabric yellowing method, and relates to the technical field of daily chemical products. 5 The fabric yellowing reagent comprises 1-3% of histidine solution and a bacterial suspension with a bacterial concentration of 1*10 5 CFU / mL-9*10 The bacteria are a mixture of one or more of Staphylococcus epidermidis and Micrococcus luteus; the solvent of the histidine solution is normal saline containing 0.15-1% of trypsin peptone; and the solvent of the bacterial suspension is normal saline containing 0.1-0.2% of trypsin soybean peptone liquid culture medium. The fabric yellowing reagent can be used for simulating fabric yellowing, and has good operability, reproducibility and data reliability.

The invention belongs to the field of in-vitro diagnostic reagents, and particularly relates to application of a reagent for detecting biomarkers in serum in preparation of a cerebral arterial thrombosis diagnostic kit. The invention determines that the concentrations of lactic acid, isoleucine, fumaric acid, ketoglutaric acid, hypoxanthine, tyrosine, histidine and inosine in serum of a cerebral arterial thrombosis (IS) patient are significantly related to major atherosclerosis (LAA) and minor artery occlusion (SAO), so that the concentrations of the biomarkers can be used as a basis for diagnosing IS and distinguishing LAA and SAO.

This invention discloses a *Trichoderma parareesei* strain for synthesizing ergothioneine and its applications, belonging to the fields of genetic engineering and bioengineering technology. This invention achieves heterologous ergothioneine synthesis by expressing *TrEGT1* and *TrEGT2* derived from *Trichoderma parareesei* in *Trichoderma parareesei*. By screening different promoters driving *TrEGT1* and *TrEGT2*, the optimal ergothioneine synthesis gene combination was obtained. Further, multiple copies of the gene combination were integrated, and the synthesis of precursor histidine was enhanced to improve the ergothioneine synthesis capacity of *Trichoderma parareesei*, achieving a shake-flask fermentation yield of 1200±12.3 mg / L and a 5L fermentation tank yield of 8.6 g / L. This invention integrates a heterologous metabolic pathway into *Trichoderma parareesei*, achieving high-efficiency ergothioneine production and facilitating low-cost, large-scale production of ergothioneine and its products.

The invention provides fusion protein containing snake venom protein and application of the fusion protein in biosynthesis of stable isotope labeled snake venom protein, and belongs to the technical field of genetic engineering and protein preparation. The fusion protein comprises a 6-poly-histidine tag, a fusion tag, a restriction enzyme cutting site of WELQ protease and snake venom protein which are connected in sequence. According to the fusion tag, the solubility of the snake venom protein fusion protein can be improved; the 6-poly-histidine tag and the fusion tag can be removed through enzyme digestion of WELQ protease, the enzyme digestion removal effect is good, and the natural structure and activity of the snake venom protein can be guaranteed; besides, a culture medium containing a unique nitrogen source or a unique carbon source labeled by an isotope is used for carrying out induction culture on recombinant bacteria for expressing the fusion protein, the fusion protein containing the target snake venom protein is subjected to induction expression, purification, WELQ protease digestion and the like are carried out, and the stable isotope labeled snake venom protein with the purity reaching 95% or above and the labeling efficiency exceeding 91% can be obtained.

The present invention relates to a composition for preventing, ameliorating or treating central nervous system diseases, comprising a peptidomimetic compound (NIP001) containing hydrophilic arginine and a hydrophobic histidine derivative. In the present invention, the peptidomimetic compound comprising hydrophilic arginine and a hydrophobic histidine derivative was confirmed to effectively inhibit inflammatory responses in microglia and to have the effect of improving the cognitive function of mice with scopolamine-induced cognitive impairment, and thus can be used as a targeted therapeutic agent for central nervous system diseases.

The invention discloses an ophthalmic preparation and application thereof. The ophthalmic preparation comprises a TNF alpha nano antibody, a protective agent, a thickening agent, a buffer solution and an optional surfactant, and pH lt is larger than or equal to 6.0 and smaller than or equal to 0; 7, 7; the protective agent is selected from at least one of trehalose, mannitol, arginine and glycine; the thickening agent is selected from any one of hydroxypropyl methyl cellulose, polyvinyl alcohol and sodium hyaluronate; the buffer solution is a phosphate buffer solution or a histidine buffer solution. The ophthalmic formulations are useful in the treatment of immune-mediated inflammatory ophthalmic diseases.

This invention belongs to the field of biomaterial preparation technology, specifically disclosing a self-assembled supramolecular peptide nanozyme material, its preparation method, and its application. The preparation method includes the following steps: S1, dissolving β-alanyl-L-histidine in ultrapure water and stirring until homogeneous to obtain solution A; S2, dissolving heme chloride in dimethyl sulfoxide and stirring until homogeneous to obtain solution B; S3, mixing solution A and solution B until homogeneous, adjusting the pH, heating in a water bath, incubating at room temperature, centrifuging, discarding the precipitate, and retaining the supernatant; S4, lyophilizing and grinding the supernatant obtained in S3 to obtain the self-assembled supramolecular peptide nanozyme material. This invention discloses a self-assembled supramolecular peptide nanozyme material, its preparation method, and its application. This supramolecular peptide nanozyme, when applied to food quality and safety testing, can achieve visual and sensitive colorimetric detection of biogenic amines in spoiled food.