36 results about "Protein crosslinking" patented technology

The invention discloses a mycosporine-like amino acid-protein cross-linked compound as well as a preparation method and application thereof, the structural formula of the mycosporine-like amino acid-protein cross-linked compound is as shown in the following formula (I): # imgabs0 # (I), in the formula (I), R is-CH2OH or-CH (OH) CH3, and the amido bond connection curve represents the peptide chain of the protein. The invention further discloses a hydrogel prepared from the mycosporine-like amino acid-protein cross-linked compound. The invention also discloses application of the mycosporine-like amino acid-protein cross-linked compound or the hydrogel in preparation of ultraviolet protection, anti-aging, wound management biological scaffolds, anti-inflammation, skin repair or hair care products and application in development of biological materials, medical dressings or cosmetics.

The present invention generally pertains to methods of characterizing crosslinking sites of a protein of interest. In particular, the present invention pertains to the use of size exclusion chromatography, peptide mapping and subunit analysis to identify and quantify crosslinking sites of a protein of interest and determine a contribution of crosslinking to the formation of high molecular weight species.

The invention relates to the technical field of biological medicines, in particular to a preparation method of protein cross-linked nano affinity microspheres, which comprises the following steps: preparing carboxylated silicon dioxide nano microspheres with the particle size of 500nm by adopting a sol-gel method, mixing tetraethoxysilane and ammonia water according to the volume ratio of 1: (3 + / -1), reacting in an ethanol solution at 40 DEG C for 6 hours, filtering, washing, and drying to obtain the protein cross-linked nano affinity microspheres. And centrifuging to obtain a microsphere precipitate, washing with deionized water for three times to finally obtain a nano microsphere suspension of which the surface is rich in carboxyl, and controlling the solid content to be 10 + / -0.5 mg / mL. The capturing efficiency of the finally prepared protein cross-linked nano affinity microspheres for exosomes reaches 95.0%, the binding capacity reaches 28.5 mu g / mg, the purity of the extracted exosomes is higher than that of an ultracentrifugation method, the biological activity and structural integrity of animal cell exosomes and plant cell exosomes are completely kept, and the protein cross-linked nano affinity microspheres are suitable for large-scale industrial production. The problems that in a traditional exosome extraction method, the recovery rate is low, impurity pollution is serious, exosome activity is damaged, and the application range is limited are solved.

A virus conjugate comprising a genetically-modified adeno-associated virus (AAV), wherein the virus is mutated to incorporate an engineered amino acid in a site-specific manner and a genetically-modified protein of interest, wherein the protein is mutated to incorporate an engineered amino acid in a site-specific manner, wherein the engineered amino acids can further comprise orthogonal bioconjugation groups suitable for attachment of a bifunctional linking reagent, whereby the virus and protein are cross-linked via the bifunctional chemical linker reagent to form a virus conjugate is described.

The invention provides a method for crosslinking and marking biomolecules in living animals based on photocatalysis. According to the method, the hydrophilic up-conversion nano composite material and the photosensitizer are in contact with the biological sample to be detected, and the target position of the biological sample to be detected is subjected to near-infrared light irradiation, so that the RNA-RNA binding protein compound is formed in situ at the target position of the biological sample to be detected, and the biological sample is obtained. Especially in situ crosslinking of RNA and RNA binding proteins in an organism. On the basis of the cross-linking method, marking, enrichment and analysis of all kinds of RNA-RNA binding protein compounds and RNA binding proteins can be realized by further matching with a compound as shown in a formula 1, and the method has broad spectrum; meanwhile, pollution caused by cross-linking of protein and protein and cross-linking of DNA and protein is effectively avoided, and high specificity is achieved.

The invention relates to the technical field of vascular therapy, in particular to a nano-drug and a preparation method thereof.The nano-drug comprises a nano-carrier, a therapeutic drug and cross-linked protein are loaded on the nano-carrier, the cross-linked protein is at least partially loaded on the surface of the nano-carrier, and the cross-linked protein is at least one of silk fibroin, sericin and silk fibroin peptide; the therapeutic drug is at least partially loaded in the nano-carrier. On one hand, cross-linked protein on the surface of the nano-carrier is promoted to be cross-linked with protein in a blood vessel by initiating the photosensitive cross-linking agent, and the nano-carrier is anchored in the blood vessel, so that the risk that nano-drug particles are eluted from the blood vessel wall is greatly reduced; on the other hand, cross-linking of cross-linked protein on the surface of the nano-carrier can be promoted by initiating the photosensitive cross-linking agent, so that the surface of the nano-carrier is gelatinized, the slow release speed of the nano-drug anchored in the blood vessel is more lasting, and further effective drug concentration can be maintained for a long time, restenosis of the blood vessel is inhibited, and the treatment effect is improved.

The invention relates to a method for improving the gel quality of skipjack surimi by using vegetable protein, and belongs to the technical field of surimi product processing. The method for improving the gel quality of the skipjack surimi by using the vegetable protein comprises the following steps: sequentially performing air chopping, salt blending, vegetable protein adding, mixing, chopping and moisture adjusting on skipjack meat at 4-10 DEG C to obtain mixed surimi; and filling a mold with the mixed surimi, carrying out heating shaping, and then carrying out ice water cooling to room temperature so as to obtain the surimi gel. The influence of different types and different contents of vegetable proteins on the quality of specific surimi gel is compared, and a proper amount of vegetable proteins are added to promote protein crosslinking so as to improve the strength, texture, water binding capacity and other gel properties of the surimi gel, so that the problems of insufficient strength and poor water binding capacity of the existing skipjack surimi gel are solved, and the skipjack surimi gel has a good application prospect. Therefore, technical support is provided for development of high-quality skipjack surimi products, and the skipjack surimi product has a wide application prospect.

Compositions and methods stabilize existing or imparted vascular states of blood vessels. In an example, a composition for vascular stabilization can include a crosslink breaker, a protein denaturant, a crosslinking agent, or some combination thereof provided the composition includes at least the crosslink breaker or the protein denaturant if the composition includes the crosslinking agent. The crosslink breaker breaks existing protein crosslinks in a luminal wall of a blood vessel. The protein denaturant denatures proteins in the luminal wall of the blood vessel. The crosslinking agent establishes new protein crosslinks in the luminal wall of the blood vessel. The composition can be formulated into a formulation for direct administration to the luminal wall of the blood vessel by an intravascular medical device to stabilize an existing vascular state of the blood vessel or an imparted vascular state of the blood vessel.

The invention relates to the technical field of preservatives, in particular to a natural compound efficient antibacterial preservative and a preparation process thereof. The preparation process comprises the following steps: preparing a loading liquid; preparing a silk solution; and preparing the natural compound efficient antibacterial preservative. Folic acid, TG enzyme and NHS are compounded and then mixed with carboxymethyl chitosan to prepare a load solution, the TG enzyme is activated through folic acid, so that the TG enzyme and NHS play a combined role, the protein crosslinking efficiency and stability are improved, the load solution can load propolis and silk at the same time, the propolis-silk compound is formed, and the propolis-silk compound is used for preparing the propolis-silk compound. The propolis and the silk are prepared into a composite copolymer through the loading liquid, the silk fiber can be prepared as a framework, the propolis can be kept in the loading liquid in a three-dimensional structure, the propolis has good antibacterial and antiseptic functions, the propolis existing in the three-dimensional structure can make contact with food as much as possible, and therefore the antibacterial and antiseptic capacity is improved; therefore, the shelf life of the food is prolonged.

The invention discloses a method for identifying a protein cross-linking mass spectrum peptide fragment pair. Comprising the steps of firstly constructing a peptide fragment vector database, then obtaining and preprocessing spectrogram data, then generating a spectrogram representation sequence, then generating a spectrogram embedding vector, then retrieving candidate peptide fragments in the vector database, and finally determining a target crosslinking peptide fragment and a crosslinking site according to a retrieval result. According to the method, the beneficial effects of remarkably improving the polypeptide segment crosslinking recognition precision and greatly reducing the candidate search space are achieved, and the method is not only suitable for traditional dipeptide crosslinking, but also capable of treating complex crosslinking forms such as tripeptide and tetrapeptide, and has high universality. Meanwhile, a retrieval framework of the vector database supports rapid updating and expansion, and the method is suitable for cross-linked mass spectrum data analysis under different species and different experiment conditions.

To provide a thickening composition with high nutritional values.SOLUTION: A thickening composition is added to foods and beverages to facilitate the deglutition of the foods and beverages. The thickening composition contains 1 mass% or more and 99 mass% or less of gelatin crosslinked with a protein crosslinking enzyme.SELECTED DRAWING: Figure 2

The invention discloses preparation and application of an anti-isotenuazonic acid nano antibody immunoadsorbent and an immunoaffinity column. The immunoadsorbent provided by the invention comprises a solid-phase carrier containing a protein cross-linking agent, and an anti-isotenuazonic acid nano antibody which is directionally coupled with the solid-phase carrier and is provided with a cysteine label at the C terminal. The nano antibody and the cysteine tag are subjected to fusion expression, directional coupling with a solid phase carrier is realized, the problem of antigen binding site occupation in traditional coupling is solved, the adsorption capacity of the immunoaffinity column is improved, the column content of the prepared immunoaffinity column reaches 905.06 ng, and the column adsorption capacity of the immunoaffinity column is improved by 202.40 ng compared with that of a non-directional coupling immunoaffinity column. And the repeated use frequency is also increased. Meanwhile, the method for detecting the isotenuazonic acid through combination with mass spectrometry has good accuracy and precision, the detection limit and the quantitation limit are lower, the sample pretreatment process is simplified, and the detection cost is reduced.

A method is provided for making a protein blocking assembly that is formed by reversibly linking a therapeutic protein to a crosslinking material. The protein blocking assembly contains a chemical structure, which is formed between the multiple bonds between the protein and the crosslinking material, that prevents the interaction of the protein blocking assembly with a second protein due to steric and / or static interference. Furthermore, administration methodologies of administering the protein blocking assembly to a subject are provided, where the protein is cleaved from the protein blocking assembly during or after administration.

A purpose is to provide a protein crosslinking agent which can be easily used. A protein crosslinking agent for a protein having a β-sheet structure is provided, comprising a structural unit derived from one selected from the group consisting of polyethylene, polyvinyl alcohol, polyamine, polyamide, polyester and polyether, and a group containing an aromatic ring, wherein the group containing an aromatic ring has at least one selected from the group consisting of a benzothiazole group, a benzoxazole group, a benzimidazole group and a naphthylazo group, each of which may have a substituent.

Disclosed herein is the use of DNA aptamer assemblies of varying DNA length, structure, and sequence to both bind to collagen and other proteins, to then act as a biocompatible, degradable, reversible, or permanent 3D crosslinkers between proteins, and to service as a biologically functional material when using the appropriate aptamer sequence. Therefore, disclosed herein are compositions comprising collagen fibers crosslinked with DNA aptamers. Also disclosed are devices and implants made from or coated with collagen fibers crosslinked with DNA aptamers. Also disclosed are methods of making collagen fibers. Also disclosed are kits for producing collagen fibers. Also disclosed herein are compositions DNA aptamers in a collagen fiber matrix that stabilizes the DNA aptamer.

The present application has an object to provide a novel protein cross-linking method. By allowing both an oxidoreductase such as laccase and a protein deamidase such as protein glutaminase to act on a substrate protein, a cross-linking reaction is promoted.

The invention provides a probe capable of being used for arylation cross-linking modification of protein nucleophilic amino acid residues. The structural general formula of the probe is shown in the formula I. The invention further provides a preparation method of the probe. The invention also provides a method for carrying out cross-linking modification on the protein by adopting the probe. The modification sites of the method are cysteine and lysine residues of the protein. Aiming at application requirements of a protein chemical selective arylation crosslinking modification technology, the invention provides an efficient and selective protein crosslinking chemical modification method based on a multi-substituent pyridinium salt active functional group, and the method is suitable for crosslinking analysis of cysteine and lysine residues.

The invention is applicable to the technical field of cell engineering, and provides a preparation method and application of a multifunctional glycoprotein photo-crosslinking agent, and according to the method, a biotin group type crosslinking agent containing a trifluorobis (acridine) photo-reaction active group, an oxamine sialic acid specific recognition group, a chain length-adjustable polyethylene glycol chain and a disulfide bond cleavable is prepared. The prepared multifunctional glycoprotein photo-crosslinking agent can realize efficient photo-induced protein crosslinking, and the structural design of the multifunctional glycoprotein photo-crosslinking agent is beneficial to subsequent protein decrosslinking and protein compound identification. By utilizing a trifluoro-bis-acridine photoreaction active group, the trifluoro-bis-acridine photo-crosslinking polymer has excellent photo-crosslinking activity; specific recognition and reaction on a sialic acid-containing sugar chain are realized by using an oxygen amine group; a polyethylene glycol chain with adjustable chain length is utilized to improve the solubility and biocompatibility, and cytoplasm pollution is avoided as far as possible; by utilizing biotin groups of disulfide bonds, efficient enrichment is realized, and the biotin groups can be selectively cut under a reduction condition.

The cryo-electron microscope sample preparation kit contains an amphipathic protein and a protein crosslinking agent, or an expression vector containing a nucleic acid sequence encoding the amphipathic protein. The kit also includes an ice thickness control molecule to which an amphipathic protein is attached. The amphipathic protein may have an amphipathic α-helix structure and may be either an antifreeze protein or a type I antifreeze protein.

The present invention discloses a method for constructing a Pore-C library suitable for complex polyploid plants, which relates to the technical field of plant genetic engineering. In the present invention, plant tissues are ground into fine powder and then added to a nuclear extraction solution, while DNA and proteins are crosslinked. Nuclear precipitates are obtained through filtration and sucrose density gradient centrifugation; after washing the nuclei with 1×PBS and resuspending the nuclei with the nuclear extraction solution, Percoll density gradient centrifugation is carried out and an equal volume of 0.25 M sucrose is added to separate and obtain intact and pure nuclei; then in situ nuclear enzyme digestion, ligation, and de-crosslinking are carried out; then it is extracted twice with a DNA extraction solution, and sodium chloride, sodium acetate, and absolute ethanol are added to the supernatant to obtain DNA. The extracted DNA is 5-9 μg, which can be used for 3-7 cells on the machine, obtaining 300 G-1 T of data, greatly reducing the cost.

The present invention discloses a mycosporin-like amino acid-protein cross-linked complex and a preparation method and application thereof. The mycosporin-like amino acid-protein cross-linked complex has a structural formula as shown in the following formula (I): #imgabs0# (I); in the formula (I), R is -CH2OH or -CH(OH)CH3, and the curve connected by amide bonds represents the peptide chain of the protein. Also disclosed is a hydrogel prepared by using the mycosporin-like amino acid-protein cross-linked complex. And the mycosporin-like amino acid-protein cross-linked complex or the hydrogel is used in the preparation of ultraviolet protection, anti-aging, wound management biological scaffolds, anti-inflammatory, skin repair or hair care products, as well as in the development of biomaterials, medical dressings or cosmetics.

The purpose of the present application is to provide a technique to improve softening of a plant protein-containing product by addition of phytase during the production of the product. The present application discloses, as an embodiment, a method for producing a plant protein-containing product, the method comprising: (1) a step for adding a phytic acid-degrading enzyme to a production raw material; and (2) a step for adding, to the production raw material, an enzyme that contributes to the formation of a protein crosslinking structure.

The invention discloses an effective diffusion coefficient model of medium-low salt pickled pigskin based on seepage and fractal double theories and application thereof, through the model constructed based on the double theories, the prediction precision and reliability are remarkably improved, the limitation of a single theory is broken through, and through the combination of the seepage and fractal theories, the effective diffusion coefficient of the medium-low salt pickled pigskin is obtained. The prediction of the model on the effective diffusion coefficient is closer to the actual pickling process; the critical protein crosslinking density is introduced, so that the phenomenon that the effective diffusion coefficient is sharply reduced when the crosslinking density is close to a critical value can be accurately described, and the prediction deviation of a traditional model in a critical state is avoided; according to the method, the geometric fractal dimension of the pigskin is obtained through a box counting method, then the fractal index is determined, the influence of surface area change caused by swelling on a diffusion interface is more scientifically quantified, and the prediction precision of the model in the dynamic process is improved.

The present invention relates to a preparation process of frozen corn dough, and belongs to the technical field of food processing. First, corn flour is subjected to alkali heat treatment, and then sieved and used as raw material, and water, enzyme and other ingredients are added. Frozen corn dough can be prepared through enzyme treatment, frozen storage, thawing and shaping, baking and other processes. The preparation method of the present invention adopts enzyme preparation combined with alkali heat treatment, improves the gelatinization characteristics of corn flour and promotes protein cross-linking polymerization, thereby improving the processing characteristics of corn dough and delaying the quality deterioration of corn dough during frozen storage. The hardness, baking loss and aging rate of corn rolls made from the frozen corn dough are reduced, the taste is soft and elastic, and the storage stability is improved, which meets consumers' expectations for corn tortilla products.

This application discloses a method for preparing water-saving surimi gel based on polyphenol-enzyme synergistic crosslinking and its application. The method includes: rinsing surimi raw materials no more than twice; sequentially adding EGCG and TGase to the rinsed surimi, utilizing their synergistic effect to induce protein crosslinking; and then filling and undergoing two-stage heating gelation to obtain the surimi gel. This application significantly improves the breaking strength, elasticity, water-holding capacity, and other textural properties of the surimi gel by introducing synergistic crosslinking of EGCG and TGase into the water-saving rinsing process, successfully overcoming the quality degradation problem caused by reduced rinsing. Simultaneously, the gel exhibits unique digestive-resistant and slow-release properties, delaying protein hydrolysis in the early stages of gastric digestion and ensuring the full release of essential amino acids, thus preserving its nutritional value. This application provides an effective solution for developing high-quality, high-nutrition, and environmentally friendly novel surimi products.

A kit for preparing a sample for a low-temperature electron microscope is provided with an amphiphilic protein and a protein cross-linking agent, or contains an expression vector that encodes an amphiphilic nucleic acid. A kit for preparing a sample for a low-temperature electron microscope is provided with an ice thickness control molecule to which an amphiphilic protein is bound. The amphiphilic protein may have an amphiphilic alpha helical structure. The amphiphilic protein can be anti-freezing protein and can also be I-type anti-freezing protein.

The problem addressed by the present invention is to provide an enzyme agent for protein deamidation and protein crosslinking containing an enzyme having protein deamidation activity and transglutaminase activity, and the use thereof. The present invention provides an enzyme agent for protein deamidation and protein crosslinking that contains as an active ingredient an enzyme having protein deamidation activity and transglutaminase activity comprising an amino acid sequence having 90% or more sequence identity with the amino acid sequence of SEQ ID NO: 1.

The technical problem of this invention lies in providing a novel protein cross-linking method. This method promotes the cross-linking reaction by allowing both oxidoreductases such as laccase and protein deamidases such as protein glutaminase to act on the substrate protein.

The invention relates to the technical field of deep processing of aquatic products, in particular to a method for improving DHA fish sausage gel strength and application thereof. Comprising the following steps: constructing a composite gel reinforcing system; mixing the minced fillet with a composite cross-linking agent and DHA (docosahexaenoic acid) emulsion; adding salt, mixing and kneading, and filling the sausage; and gradient thermal induction: cooling and shaping to obtain the DHA fish sausage. By adopting the synergistic effect of the composite cross-linking agent and the emulsion stabilizer and combining with a gradient thermal induction process, a protein cross-linked network is optimized, a DHA protection system is constructed and a precise regulation and control processing technology is adopted, DHA oxidative damage is inhibited, meanwhile, a protein three-dimensional network structure is enhanced, synergistic improvement of the gel strength and the nutrition function is achieved, and the nutritional value of the product is improved. And the technical bottleneck of the traditional process is broken through.