364results about "Enzyme stabilisation" patented technology

The invention discloses a polypeptide ligand for improving the thermal stability of MMLV reverse transcriptase and application of the polypeptide ligand, and relates to the technical field of biology. The invention specifically discloses a polypeptide ligand with an amino acid sequence as shown in SEQ ID NO: 1. The polypeptide ligand can obviously improve the thermal stability of MMLV RT. After being combined with the polypeptide ligand, the MMLV RT can effectively maintain the activity of the MMLV RT at 45-60 DEG C and maintain good activity in a freeze-thaw cycle, and the Ct value change is small after the MMLV RT is placed at 37 DEG C for more than 15 days, so that the polypeptide has a very good application prospect in industrial production and commercial application.

The invention discloses a bacterium-enzyme mixed preparation for PET plastic degradation and a preparation method thereof, and belongs to the technical field of enzyme preparations, a lanthanum metal framework is formed, loaded on the surface of titanium dioxide and carbonized to obtain a lanthanum-doped porous carbon layer, and then nitric acid treatment and silane coupling agent treatment are performed to significantly increase the specific surface area and roughness, so that the specific surface area is increased; the calcium-based diatomite is taken as a carrier to form a sodium alginate microcapsule taking an enzyme preparation as an inclusion, and the sodium alginate microcapsule is loaded on the surface of the calcium-based diatomite, so that the situation that titanium dioxide generates hydroxyl free radicals in photocatalysis to directly attack the enzyme preparation is avoided, and the degradation effect on the PET plastic is prolonged; calcium ions in the calcium-based diatomite can increase the crosslinking degree with the sodium alginate, the load rate of the sodium alginate microcapsule is increased, the strength of the microcapsule is improved, and the slow release effect of an enzyme preparation in the microcapsule is further improved.

The invention belongs to the technical field of bioengineering and food safety, and particularly relates to a fusion enzyme for degrading aflatoxin B1 (AFB1) and / or zearalenone (ZEN) and application of the fusion enzyme. The fusion enzyme S1-AsDPP III disclosed by the invention can effectively degrade AFB1 and ZEN, the fusion enzyme is obtained by fusing a section of self-assembled amphiphilic oligopeptide S1 sequence at the N end of wild type AsDPP III, and the thermal stability of the fusion enzyme and the amphipathy of the fusion enzyme in an oil-water coexistence system can be remarkably improved. Under mild reaction conditions, the fusion enzyme can efficiently degrade AFB1 and ZEN in vegetable oil, and is especially suitable for detoxification treatment of common edible oil such as peanut oil and corn oil. The invention provides a green, safe and efficient scheme for removing fungaltoxin from grease food, and the method has a good industrial application prospect.

According to the scheme, the invention provides the recombinant macrolide enzyme as well as the preparation method and the application thereof, the amino acid sequence of the recombinant macrolide enzyme is as shown in SEQ ID NO.1, and the recombinant macrolide enzyme is derived from an EreC esterase family of enterobacter hormaechei and is obtained through site-specific mutagenesis; the mutation sites are as follows: glutamic acid at the 44th site is mutated into asparagine, tyrosine at the 55th site is mutated into proline, proline at the 76th site is mutated into arginine, phenylalanine at the 153rd site is mutated into alanine, and serine at the 219th site is mutated into glutamic acid. The method is expected to remove macrolide antibiotic pollution, and has good economic benefits and practical values.

The invention discloses a polypeptide ligand of MMLV reverse transcriptase and application of the polypeptide ligand, and relates to the technical field of biology. The invention specifically discloses a polypeptide ligand with an amino acid sequence as shown in SEQ ID NO: 1, the stability of MMLV reverse transcriptase can be remarkably improved, the MMLV reverse transcriptase can be placed at 37 DEG C for more than 15 days, and the Ct value difference is lower than 2; in addition, the MMLV reverse transcriptase activity can be maintained under a high-temperature condition (45-60 DEG C); the activity loss of the MMLV reverse transcriptase in a freeze-thaw cycle is reduced, and the industrial production and commercial application of the MMLV reverse transcriptase are effectively promoted.

The invention relates to the technical field of pepsin preparation, in particular to a chemical modifier and a method for preparing pepsin through the chemical modifier, a novel composite modifier Mal-PEG-CMC is synthesized, and the modifier with good water solubility and high coupling rate is obtained by optimizing the molecular weight of PEG, the molar ratio of PEG to maleic anhydride, the substitution degree of CMC and the coupling ratio; the chemically modified pepsin is prepared based on the modifier, and the modified pepsin is obtained through the steps of pepsin purification, sulfydryl exposure through DTT pretreatment, targeted modification reaction and purification. The performance of the modified pepsase is remarkably improved, the pepsase is suitable for animal source and recombinant expression pepsase, the application bottleneck of natural enzyme is effectively broken through, and the pepsase has important value in the fields of food processing, medicine and the like.

The invention discloses an anti-Taq DNA polymerase antibody or an antigen binding fragment thereof and application thereof, and relates to the technical field of biology. The antibody or the antigen binding fragment of the antibody can be specifically bound with Taq DNA polymerase, the polymerization activity and / or excision activity of the Taq DNA polymerase are / is blocked, and the stability of the Taq DNA polymerase is improved.

The present invention relates to aqueous compositions, and more specifically aqueous compositions for replicating a nucleic acid template, wherein the composition comprises D2O, as well as to methods and uses relating to such compositions. The composition can be used, for example, in a method of storing the composition, or a method for replicating a nucleic acid template, for instance for the synthesis of Xpandomers for sequencing by expansion.

The invention relates to the technical field of cyanobacterial bloom control in water, and particularly discloses a compound enzyme-bacterium synergistic preparation for cyanobacterial bloom control, a preparation method and a use method. The preparation comprises the following components in percentage by mass: compound enzymes (10-20% of cellulase, 8-12% of beta-1, 3-glucanase and 3-8% of lipase), functional bacteria (10-20% of bacillus subtilis, 8-15% of trichoderma harzianum and 5-10% of bacillus amyloliquefaciens), an enzyme stabilizer (3-8% of trehalose), an adsorption carrier (15-25% of Fe < 3 + > modified charcoal and 8-15% of diatomite) and auxiliary components. The preparation method comprises the steps of carrier modification, solid fermentation and microcapsule embedding. During use, 3-20kg / 1000m < 3 > of water is added for the first time, 2-10kg / 1000m < 3 > of water is added every 7-14 days in the maintenance stage, and synchronous aeration is performed. Through the synergistic effect of beta-1, 3-glucanase and trichoderma harzianum, the algicidal rate is 92%, and the spore germination inhibition rate is 82%; the Fe < 3 + > modified charcoal improves the stability of the enzyme in an alkaline environment (80% of activity is retained when the pH value is 9); the method is suitable for eutrophic water with chlorophyll a greater than or equal to 30 [mu] g / L, and has no chemical residue risk.

The present compositions and methods relate to thermostabilization of phytase with phosphate and increasing the recovery of phytase during the production of heat-treated food or animal feed pellets that contain phytase.

The present invention proposes a method and use for stabilizing a simple agglomerate for pH and salt and with adjustable size. In phosphoric acid buffer solutions with different salt concentrations and pH values, the polyacrylic acid hydroxypropyl group condensation body has specific stability; hydrophobic thermal response blocks are introduced into a hydroxypropyl acrylate monomer through reversible addition-fragmentation chain transfer polymerization to regulate and control the size of a condensation body, and a phase separation behavior is shown at different temperatures; a hydrophobic block without thermal response is introduced to regulate and control the size of the aggregate, and no thermal response behavior is shown. Continuous regulation and control of the size of the aggregate from the micron level to the nano level are achieved, and the requirements of different application scenes are met. The hydroxypropyl polyacrylate condensation body can be used for packaging various dyes and drugs; high-efficiency enzyme protection is achieved, formed aggregates can protect glucose oxidase, and the retention rate of enzyme activity reaches 85% or above after treatment is conducted for 3 hours at 60 DEG C; as a micro-reactor for the reaction of generating p-nitrobenzaldehyde phenylhydrazone from p-nitrobenzaldehyde and phenylhydrazine, the reaction rate is greatly improved.

The present invention relates to methods and cross-linkers for the macrocyclization of proteins. The invention is useful for increasing the stability of a protein.

The present invention relates to novel enzyme nanoparticles capable of converting methane into methanol, in which key active sites of methane-oxidizing bacteria are fused with each other and expressed on a protein that can be self-assembled in cells to form nanoparticles, and specifically to enzyme nanoparticles including a protein having methane monooxygenase (MMO) activity and active sites of the methane oxidase, a method for production thereof, a recombinant microorganism into which a nucleic acid encoding the protein and the active site of the methane oxidase is introduced, and immobilized enzyme nanoparticles including the enzyme nanoparticles loaded on a carrier.

The present application relates to the technical field of small molecule peptide preparation, and specifically discloses a preparation process of selenium-rich antioxidant pig lung polypeptide. The preparation process of the selenium-rich antioxidant pig lung polypeptide comprises the following steps: washing and decontaminating fresh pig lung, peeling off the trachea, removing grease, and twisting into a minced meat shape to obtain pig lung pre-preparation material; mixing the pig lung pre-preparation material with a vitamin C aqueous solution, adding nano-silicon dioxide powder and eugenol to the mixture, and performing ultrasonic treatment; cooling to-10 to-30 DEG C, keeping for 1 to 2 hours, and then increasing the temperature to room temperature; homogenizing treatment, filtration, collecting the precipitate, and obtaining pretreated pig lung; adding water to the pretreated pig lung and stirring until uniform; adjusting the pH value of the system; adding a stabilizing alkaline protease for treatment; adjusting the system to be neutral; adding a neutral protease for enzymolysis; and cooling to room temperature to obtain pig lung enzymolysis liquid; centrifuging the pig lung enzymolysis liquid, ultrafiltering, collecting the permeate, nanofiltrating, collecting the concentrated liquid, and drying.

The invention belongs to the technical field of bioengineering, and particularly provides a stable liquid alkaline protease preparation which comprises liquid alkaline protease, NaCl, polysaccharide and histidine. Based on the mass of the liquid alkaline protease, the addition amount of NaCl is 5%-10%, the addition amount of polysaccharide is 0.1%-0.5%, and the addition amount of histidine is 0.02%-0.1%. According to the stable liquid alkaline protease preparation provided by the invention, NaCl, polysaccharide and histidine are added into alkaline protease, filtration and sterilization are performed after pH is adjusted, the stability of the liquid alkaline protease is obviously improved, heat preservation is performed for 6 months at the temperature of 45 DEG C, and the enzyme activity is basically free of loss. The preparation has simple components and is especially suitable for feed and food industries.

Disclosed are compositions, methods, and kits for modifying DNA within cells as well as compositions and methods for modifying gene expression in a cell. In particular, the invention generally relates to compositions, methods, and kits for DNA editing using single-stranded DNA. Compositions and methods for modifying gene expression using artificial microRNAs (amiRNA) are also contemplated.

Provided is a method for improving the stability of urate oxidase. The inventors have discovered that combining an active ingredient urate oxidase or chemically modified urate oxidase with a stabilizer xanthine through a non-covalent bond can significantly improve the in vivo and in vitro stability of urate oxidase and chemically modified urate oxidase in the form of a tetramer, thereby effectively improving the stability of urate oxidase.

The invention belongs to the technical field of biological enzyme preservation, and particularly relates to a bromelain freeze-drying protective agent and a preparation method thereof. The trehalose and pulullan compound freeze-dried powder injection is prepared from the following components in parts by weight: 30 to 50 parts of trehalose, 8 to 10 parts of pulullan, 3 to 10 parts of maltodextrin, 12 to 22 parts of mannitol, 1 to 4 parts of sorbitol, 4 to 12 parts of glycine, 0.05 to 0.2 part of polysorbate-20, 1.5 to 4.5 parts of a buffering agent, 0.2 to 0.8 part of N-acetylcysteine, 0.05 to 0.3 part of oxidized glutathione, 0.8 to 2.5 parts of PEG (Polyethylene Glycol) and 0.05 to 0.3 part of an antioxidant. According to the invention, trehalose-pullulan is taken as a main skeleton, so that the growth of ice crystals is inhibited, and the water activity is reduced; mannitol constructs a crystal phase support network, and polysorbate-20 stabilizes an interface; sulfydryl is temporarily sealed through oxidized glutathione, and controllable reduction during redissolution is realized through microencapsulated N-acetylcysteine; and a sodium phosphate buffer system keeps the pH stable.

To provide a solid composition useful for various treatments of a hydrogen bonding material such as a biological sample.SOLUTION: A compound of formula (I) Wherein each R independently represents a linear or branched hydroxyalkyl group having one or more hydroxyl groups and an alkyl moiety having 1 to 10 carbon atoms; N represents an integer of 1 to 3. The solid composition contains the organic ammonium salt and a biological sample, wherein the mass ratio of the organic ammonium salt to the biological sample is 10:1 to 0.1:1.SELECTED DRAWING: None

Some aspects of this disclosure provide compositions, methods, systems, and kits for controlling the activity and / or improving the specificity of RNA-programmable endonucleases, such as Cas9. For example, provided are guide RNAs (gRNAs) that are engineered to exist in an “on” or “off” state, which control the binding and hence cleavage activity of RNA-programmable endonucleases. Some aspects of this disclosure provide mRNA-sensing gRNAs that modulate the activity of RNA-programmable endonucleases based on the presence or absence of a target mRNA. Some aspects of this disclosure provide gRNAs that modulate the activity of an RNA-programmable endonuclease based on the presence or absence of an extended DNA (xDNA).

The application belongs to the technical field of enzyme preparation processing, and specifically provides a preparation method of a gastric-stable enzyme preparation, which comprises the following steps: (1) placing enzyme liquid in a stirrer, adding stabilizers and carriers into the enzyme liquid, uniformly stirring, then adding emulsifiers and emulsion stabilizers, uniformly stirring again, obtaining enzyme mixture, and heating and keeping warm; (2) heating hot-melt type packaging materials to completely melt into liquid state, and keeping the packaging materials in liquid state; (3) starting the stirrer, slowly pouring the liquid hot-melt type packaging materials into the stirrer while stirring, and obtaining a material liquid; (4) spray drying the material liquid, and obtaining the gastric-stable enzyme preparation. The preparation method provided by the application effectively avoids the destruction of the prepared enzyme preparation by pepsin after the enzyme preparation enters the stomach of an animal, improves the enzyme activity retention rate of the enzyme preparation product after passing through the stomach, and further improves the stability of the enzyme preparation in the storage process, especially the storage stability in a humid environment.

[Problem] To provide a measurement reagent which contains lactate dehydrogenase, wherein the stability of the lactate dehydrogenase is improved in order to enable the measurement reagent to be used for a long period of time; and to provide a method for improving the stability of the lactate dehydrogenase. [Solution] An alkali metal compound is included in a reagent containing lactate dehydrogenase.

The application discloses a marine-derived cholesterol oxidase and a preparation method and application thereof, and relates to the technical field of biology. The amino acid sequence of the marine-derived cholesterol oxidase (SkChOx) is shown in SEQ ID NO. 1 or 3, the specific enzyme activity of the marine-derived cholesterol oxidase can reach 31.9 U / mg, the marine-derived cholesterol oxidase has excellent anti-reverse performance, maintains high stability in the pH range of 5.0-10.0, has good temperature tolerance, organic solvent tolerance and metal ion tolerance, and exhibits unique salt activation effect and salt tolerance. The enzyme is compounded with dithiothreitol (DTT) and nonylphenol polyoxyethylene ether (NP-40) to form a liquid enzyme preparation, and after incubation at 37 DEG C for 7 days under accelerated conditions, the catalytic activity of the liquid enzyme preparation still remains about 87%, the liquid enzyme preparation has excellent long-acting storage stability, and has wide application prospects in the fields of clinical diagnosis, food physical and chemical inspection, biosensor development and industrial preparation of steroid drugs.

The present application belongs to the technical field of biological enzyme preservation, and particularly relates to a bromelain freeze-drying protective agent and a preparation method thereof. The composition comprises the following components: 30-50 parts of trehalose, 8-10 parts of pullulan, 3-10 parts of malt dextrin, 12-22 parts of mannitol, 1-4 parts of sorbitol, 4-12 parts of glycine, 0.05-0.2 parts of polysorbate-20, 1.5-4.5 parts of a buffer, 0.2-0.8 parts of N-acetylcysteine, 0.05-0.3 parts of oxidized glutathione, 0.8-2.5 parts of PEG and 0.05-0.3 parts of an antioxidant. The present application takes trehalose-pullulan polysaccharide as a main skeleton, inhibits ice crystal growth and reduces water activity; mannitol constructs a crystal phase support network, and polysorbate-20 stabilizes the interface; oxidized glutathione temporarily seals mercapto groups, and microencapsulated N-acetylcysteine realizes controllable reduction during redissolution; and a sodium phosphate buffer system maintains pH stability.

The invention provides a rapid detection kit and a rapid detection method for phytosterol, and belongs to the field of food detection.The rapid detection kit for phytosterol comprises a phytosterol standard substance, a standard substance diluent, a substrate solution, an enzyme mixed solution, a stop solution and an elisa plate; the standard substance diluent comprises isopropanol or dimethyl sulfoxide; the substrate solution is prepared from TMB (Tetramethylbenzidine) and a substrate buffer solution; the enzyme mixed solution is a mixed solution of a cholesterol oxidase solution and a horse radish peroxidase solution. By optimizing the composition of each working reagent in the kit, the sensitivity and accuracy of phytosterol detection are remarkably improved. Meanwhile, the rapid detection method provided by the invention is simple and convenient to operate, short in detection time and suitable for on-site rapid detection.

The present invention relates to new polypeptides derived from arginase 2. The present invention also relates to uses of said polypeptides and compositions comprising said polypeptides.

Methods and compositions of storing a biological material are described herein. In some embodiments, these methods provide one or more advantages over current methods. For example, methods described herein can be used to prepare and process biological materials for storage at elevated temperatures. In one aspect, a method of storing a biological material comprises providing a preservation composition and exposing the preservation composition to electromagnetic radiation to form an amorphous solid matrix containing the biological material. In some embodiments, the method further comprises monitoring temperature of the preservation composition during the exposure to the electromagnetic radiation.

The present invention relates to a method for preparing an enzyme blend, the method comprising the steps of: providing a fermentation-derived preparation of a first enzyme of interest; exposing the first enzyme of interest preparation to a temperature higher than the fermentation temperature; purifying the first enzyme from the fermentation-derived preparation; and adding at least one second enzyme of interest to the purified first enzyme; thereby obtaining an enzyme blend. Furthermore, the present invention relates to an enzyme blend obtainable or obtained by the method according to the present invention.

The invention provides a liquid boron-free enzyme composition, comprising aliphatic 1,2-diols, which exhibit excellent physical and microbial stability.

An object of the present invention is to provide a lactase solution showing good permeation through a filtration filter, a lactase solution showing good permeation through a filtration filter and having a good residual lactase activity, and a lactase solution showing good permeation through a filtration filter and having a good residual lactase activity even when a lactase solution having a low protease activity and a low arylsulfatase activity as contaminant enzymes is used. A lactase solution containing any of (i) to (iii) below. (i) 0.0001 to 0.1 mass% of an unsaturated fatty acid or a salt thereof (ii) 0.0001 to 0.1 mass% of a saturated fatty acid salt (iii) 0.01 to 10 mass% of at least one selected from yeast extract, soybean peptone, pea protein, a casein degradation product, and corn steep liquor