43results about How to "Conformational stability" patented technology

The invention discloses a method of preparing S-adenosyl methionine, according to the method, by using polyhydroxyl organic reagent to keep the activity of enzyme, by taking adenosine triphosphate precursor, L-methionine and phosphate ions as a substrate and taking glucose and / or Maltose as an energy supplier, and by adding the combination of metal ions, the producing strain with permeability can be used for producing S-adenosyl methionine in the way of whole-cell biocatalysis. The invention can use the combination of metal ions to regulate the metabolism flow to improve energy self-coupling efficiency; and organic reagent is added to keep the activities of thalli and enzyme. The strain with permeability is used for producing S-adenosyl methionine, thereby shortening the synthesis time and accumulating outcomes outside cells, so that the cost of the following separation can be reduced, and the operational steps also can be simplified.

The invention provides amnion eye drops for curing cornea alkali burn and a preparation method thereof. The preparation method comprises the steps of: taking amnion homogenate supernate as main activeconstituent; and adding with trehalose, hyaluronic acid or salt thereof, heparin or salt thereof, sodium chloride, benzalkonium bromide, vitamin, etc. The eye drops belongs to an ophthalmology drug delivery system, has a good lubrication function, and can provide a conglutination-resistant surface; and the drug delivery system is added with the other pharmacological active constituents, thereby being capable of increasing the viscocity of medical liquid, prolonging the residence time of the drug in eye surface, improving the bioavailability of the drug, reducing the side effect of the drug, reducing the drug irritation, and having a slow release effect. The amnion eye drops is an effective ophthalmology new drug, and has good clinic application foreground.

The invention discloses a porcine reproductive and respiratory syndrome virus Nsp2 protein nano-antibody and an application thereof. The nano-antibody is named Nb12, and the amino acid sequence of thenano-antibody is represented by SEQ ID NO.3. A camel is immunized with a truncated expression Nsp2 recombinant protein, camel peripheral blood lymphocytes are separated, and an immunized bactrian camel VHH gene is amplified by using RT-PCR, the amplified gene is connected into a pCANTAB 5E phage vector to construct a bactrian camel heavy chain antibody variable region library, 44 Nsp2 specific nano-antibodies are screened out through three rounds of panning by utilizing a phage display technology, tests prove that the nano-antibodies can specifically react with a Nsp2 protein, and the Nb12 has strong binding force. Antiviral test results show that when the virus inoculation amount is 0.01 MOI, the nano-antibody Nb12 shows a virus replication inhibition effect on both PAM cells and Marc-145 cells. Therefore, a new technical means is provided for subsequent research of the PRRSV Nsp2 and prevention, control and diagnosis of the PRRSV.

The invention discloses a real-time warm start Taq enzyme and a preparation method thereof. The real-time warm start Taq enzyme is an antigen-antibody complex of a Taq enzyme and a Taq enzyme nano antibody through antigen-antibody reaction, wherein the Taq enzyme nano antibody is derived from but not limited by animals which can generate nano antibodies through Taq enzyme immunoassay. By forming the antigen-antibody complex, the activity of the Taq enzyme can be released only at relatively high temperature, warm start can be achieved, the specificity, the reliability and the sensitivity of the Taq enzyme are improved, generation of non-specific amplification is avoided, and the Taq enzyme is capable of reducing clone mispairing to a very large extent and achieving efficient specific amplification when being compared with similar products. The nano antibody has high affinity and high stability, is capable of greatly improving specificity, sensitivity and amplification efficiency of warm start PCR (Polymerase Chain Reaction), and is applicable to various PCR reactions.

The present invention discloses a metal complex of a biscalix[4]arene derivative, having a chemical structure represented by formula II. The complex has a small toxicity and a high biocompatibility, is suitable for being covalently combined with nucleic acids, peptides, proteins or other biological molecules to form a fluorescent probe molecule having a high fluorescence quantum ratio, a long fluorescence lifetime and a low detection limit, is suitable for biomolecule detection in cells, tissues or living organisms, and has a broad application prospect in the field of biomedicines. The invention discloses a synthesis method of the complex. The method provides multiple selection routes for the synthesis of the complex, and has the advantages of simplicity and easiness in the synthesis routes, high yield in the obtained complex, and suitableness for large-scale production preparation of the complex.

The invention belongs to the technical field of aptamer design, and particularly relates to an aptamer design method based on single-nucleotide molecular docking. Starting from an experimental structure of a target small molecule, positions of nucleotides combined around the target small molecule are obtained through hydration docking; then, the discrete nucleotides are assembled into a complete aptamer; and finally, the binding capacity of the designed aptamer and the target small molecule is detected by adopting an MST experiment. The aptamer design method in the invention has been used in the design of aptamers of toxin small molecule okadaic acid (OA); the toxin is a widely distributed marine biological toxin, and can cause diarrhea type shellfish poisoning, so that the detection of OAin marine products is of great significance to food safety; an aptamer OA-D1 targeting OA is obtained by design through a calculation method; the MST experiment verifies that the equilibrium dissociation constant of the aptamer and OA is 75.6 nM; and therefore, the calculation design method is reasonable and effective.

The invention belongs to the field of food, and particularly relates to a thymol-chitosan oligosaccharide compound, and a preparation method and application thereof. The thymol-chitosan oligosaccharide compound is a compound formed by crosslinking chitosan oligosaccharide and thymol by using an ionic crosslinking method. The thymol and the chitosan oligosaccharide are used as raw materials; according to the activity and structure characteristics of the thymol and the chitosan oligosaccharide, the thymol-chitosan oligosaccharide compound is prepared by the ionic crosslinking method; the condition that the antibacterial performance and the oxidation resistance of the compound are obviously improved is discovered; through observation by a scanning electron microscope, the condition that the thymol-chitosan oligosaccharide compound is of a spherical or blocky structure is discovered; and by analyzing the molecular structure of the compound through infrared and nuclear magnetic resonance, the conditions that thymol molecules enter hydrophobic cavities formed by the chitosan oligosaccharide and TPP through the charge effect, and the stability of the molecular structure is maintained by using hydrophobic interaction and electrostatic force between molecules are discovered. When the compound is prepared into a coating film to be sprayed on the surface of Nanguo pears, storage experiments prove that the thymol-chitosan oligosaccharide compound can obviously improve the storage and fresh-keeping properties of the Nanguo pears.

The invention discloses an aromatic aldehyde / chitosan non-covalent modified carbon nano-tube composite material and belongs to the field of nano-material science. The method comprises the following steps: firstly, modifying chitosan by aromatic aldehyde to obtain aromatic aldehyde / chitosan cross-linking product, subjecting a carbon nano tube to non-covalent modification by the aromatic aldehyde / chitosan cross-linking product to obtain the carbon nano-tube composite carrier. The aromatic aldehyde / chitosan non-covalent modified carbon nano-tube composite material has good adsorption capacity on enzyme, meanwhile the enzyme activity can be kept at a high ratio, and the composite material has a wide application prospect in the field of immobilized enzyme carriers. The preparation method of the carbon nano-tube composite carrier material is simple in process, short in preparation period and mild in the reaction conditions, the requirement on equipment is low, the energy consumption is low, and the method is suitable for industrial production.

The invention discloses a metal complex of a double-cup[4]aromatic hydrocarbon derivative. The metal complex has a chemical structure as shown in formula II. The complex is small in toxicity, high inbiological compatibility, suitable for being covalently combined with biological molecules such as nucleic acid, peptide or proteins to form a fluorescent probe molecule with high fluorescent quantumrate, long fluorescent service life and low detection limit, suitable for detecting the biological molecules in cells, tissues or living bodies and wide in application prospect in the field of biological medicine. The invention discloses a synthetic method of the complex, provides various selection ways for the synthesis of the complex, is simple and easy in synthesizing a route, high in yield ofprepared complex and suitable for the mass production of the complex.

The present invention relates to diagnostic imaging and in particular to the diagnostic imaging of fibrosis. More particularly, the present invention provides a polypeptides, cyclic polypeptides and pharmaceutical compositions suitable for the non-invasive visualization of fibrosis. The polypeptide of the invention may comprise an amino acid sequence consisting of: X1-X2-M-H-G-L-X7-L-X9-X10-D-E wherein amino acid X1 is R, F or P; amino acid X2 is F or V; amino acid X7 is Q, H or L; amino acid X9 is W or G and amino acid X10 is A or D.

The invention relates to a molecular imprinting microsphere material for selective recognition of multiple target proteins and a preparation process of molecular imprinting microsphere material. According to the molecular imprinting microsphere material, specific peptide fragments corresponding to the multiple target proteins are used as template molecules, a high-molecular polymer is used as a matrix, and the molecular imprinting microsphere material is prepared by a polymer phase inversion method. The molecular imprinting microsphere material is used for selective recognition of standard target proteins.

The invention provides a preparation method of synaptic vesicle protein SV2A. The preparation method comprises the following steps: 1) overexpression: transferring the 104th-742nd basic groups of a human SV2A gene with a label for protein affinity purification into an animal cell through a virus vector to overexpress the animal cell; (2) dissolving: cracking the animal cell, and dissolving membrane protein by using an excessive mixed solution of n-dodecyl beta-D-maltitoside and cholesterol hemicellulose succinate relative to the membrane protein, wherein the mass concentration ratio of the n-dodecyl beta-D-maltitoside to the cholesterol hemicellulose succinate is 10: 1; and 3) purification: performing centrifuging, taking supernate, performing purifying by affinity chromatography, replacing n-dodecyl beta-D-maltitoside and cholesterol hemicellulose succinate trisalt in the protein solution by using a digitonin solution which is excessive relative to the membrane protein, and performing purifying again by using a molecular sieve to obtain the SV2A protein. According to the method, the SV2A protein with stable configuration can be successfully separated.

The invention belongs to the field of organic synthetic medicines, and concretely relates to a small molecular oxothiazine derivative. The general formula is shown in the specification. The small molecular oxothiazine derivative can be used as a forward allosteric regulator of an AMPA receptor, and the compound is proved to be capable of positively regulating the AMPA receptor, so that the conformation after an agonist (such as endogenous neurotransmitter glutamic acid) is combined with the receptor is more stable, the inactivation rate of the receptor is reduced, the desensitization of the receptor is inhibited, and the function of the AMPA receptor is enhanced.

A header for use in heat exchanger includes a base wall (20) with a plurality of tube insertion apertures (23), an opposite wall (30) opposed to the base wall (20), a pair of side walls (40a and 40b) disposed at both lateral sides of the base wall (20) and the opposite wall (30) and connecting the lateral sides and are inforcing walls (50a and 50b) disposed betwwen the base wall (20) and the opposite wall (30) along a longitudinal direction thereof and connecting the base wall (20) with the opposite wall (30). The side walls (40a and 40b) are integrally formed at both lateral sides of the base wall (20) be bending processing. A first half (30a) of the opposite wall (30) is integrally formed at a side of one of the side walls (40a) by bending processing, and a second half (30b) of the opposite wall (30) is integrally formed at a side of the other of the side walls (40b) by bending processing. Reinforcing walls (50a and 50b) are integrally formed at sides of the first half (30a) and the second half (30b) of the opposite wall (30) by bending processing. With this header for use in heat exchanger, high pressure resistance can be obtained, and the number of parts and the manufacturing cost can be decreased.

The invention relates to extraction, preparation and detection of biological substances, in particular to a cell lysate, a method for extracting intracellular proteins such as a Toxoplasma membrane antigen by using the cell lysate, and a kit employing the Toxoplasma membrane antigen, belonging to the field of in-vitro diagnostic reagents. The cell lysate of the invention includes amino acids, denaturants, carbohydrates and alcohols. Compared with the prior art, the invention has the advantages that intracellular proteins are fully released and a recovery rate is increased since a novel formulafor the lysate is adopted, so the sensitivity and specificity of clinical diagnosis and detection are improved. At the same time, the novel lysate of the nvention promotes tight folding of proteins,stabilizes the conformations of proteins, enhances the thermal stability of proteins, and ensures stable storage of detection reagents.

The invention relates to corn SOD molecule finishing method. Its features are that finishing agent and weight proportion are as follows: polyethylene glycol 8, anhydrous sodium sulfate 1, cyanogens urea acyl chloride 1, and anhydrous benzene 6.6; water and fat solubility polymers polyethylene glycol is used as the main finishing agent; the cyanogens urea acyl chloride is used as activator. The manufacturing method is simple. And it can increase stability, prolong half life, remove immunizing source and toxicity, increase film permeability, improve biochores and metabolism behavior, and increase solubility and organic solvent proof denaturing to make corn SOD can be extensively applied to food service, light, and medicine industries.

The present invention relates to the use of Stefin A as a scaffold protein for the display of inserted peptides, particularly wherein the Stefin A is a human Stefin A. Several mutations are advantageously made in the wild type stefin A sequence to improve it as a scaffold; preferably the Stefin A comprises a heterologous peptide insertion at the Leu 73 site. Furthermore, preferably the scaffold protein comprises a V48D mutation; preferably the scaffold protein comprises a G4W mutation. Preferably the scaffold comprises Leu73, V48D and G4W mutations. The invention also relates to the scaffold proteins themselves, in particular a stefin A polypeptide having the Leu73, V48D and G4W mutations, such as shown as SEQ ID NO: 1. The invention also relates to a method for identifying binding proteins and to peptide A (RLNKPLPSLPV) and its use in treating yeast infections.

The invention discloses a baclofen artificial hapten, an artificial antigen as well as a preparation method and application thereof. The molecular structural formula of the baclofen artificial haptenis represented by a formula (I), and the molecular structural formula of the baclofen artificial antigen is represented by a formula (II). According to the baclofen artificial hapten, the characteristic structure of baclofen is reserved to the maximum extent, and the baclofen artificial hapten has an active group capable of being coupled with carrier protein and can be used as an antigen determinant; the further prepared baclofen artificial antigen can be used for immunizing to obtain an anti-baclofen antibody with high affinity, high sensitivity and strong specificity, the titer of immune serum obtained by immunizing New Zealand white rabbits is up to 1:80000, and the antibody can be used for carrying out rapid and accurate immunodetection and immunoassay on baclofen.

The invention belongs to the field of organic synthetic medicines, in particular relates to an oxothiazine compound. The general formula is shown in the specification, the oxothiazine compound can beused as a forward allosteric regulator of an AMPA receptor; the compound is proved to be capable of positively regulating the AMPA receptor, so that the conformation after an agonist (such as endogenous neurotransmitter glutamic acid) is combined with the receptor is more stable, the inactivation rate of the receptor is reduced, the desensitization of the receptor is inhibited, the function of theAMPA receptor is enhanced, the drug-likeness of the AMPA receptor is remarkable, and the market prospect is wide.

The invention discloses an aromatic helical foldamer as well as a preparation method and application of the aromatic helical foldamer. The aromatic helical foldamer provided by the invention is dimethyl8,8'-((8,8'-(((pyridine-2,6-dicarbonyl)bis(aza-2-yl))bis(carbonyl))bis(4-isobutoxyquinoline-2,2'-carbonyl))bis(nitroalkyl-2-yl))bis(4-(2-(tert-butoxy)-2-oxyethoxy)quinoline-2-tert-butyl carboxylate.A synthesis method comprises the steps: firstly, preparing 8,8'-((pyridine-2,6-dicarbonyl)bis(aza-2-yl))bis(carbonyl))bis(4-isobutoxyquinoline-2-carbonyl chloride, and then, preparing the target aromatic helical foldamer. At present, a helical structure shows an unprecedented potential in the fields such as chiral separation, molecular recognition and display material, the aromatic helical foldamer is successfully synthesized, and novel thoughts and approaches are provided for the construction of an aromatic helical structure.

The invention discloses a millimeter-scale macroporous-mesoporous carbon sphere / cup [4]-double crown-6 interpenetrating composite material which is obtained by directionally polymerizing cup [4] arene-(benzo) crown-6-(phenylmethyl methacrylate) crown-6 to the inner surface and the outer surface of a millimeter-scale macroporous-mesoporous carbon sphere. The structural formula of the cup [4] arene-(benzo) crown-6-(phenylmethyl methacrylate) crown-6 is shown in the specification. The invention further discloses a preparation method of the millimeter-scale macroporous-mesoporous carbon sphere / cup[4]-double crown-6 interpenetrating composite material, the preparation method is simple, and the obtained millimeter-scale macroporous-mesoporous carbon sphere / cup [4]-double crown-6 interpenetrating composite material can be used for adsorbing and separating radionuclide Cs and is excellent in adsorption and separation effect.

In a fastener tape woven with transparent or semi-transparent synthetic fiber monofilament yarn as warp yarn (2) and weft yarn (3), a plural of flexible yarns (6) are interwoven into a side edge portion (5) of the fastener tape (1) in a longitudinal direction of the tape (1) so as to form a fastener-element-mounting portion (10) for mounting fastener elements (14). The fastener-element-mounting portion (10) may be formed of an interwoven portion (11) having a flat surface, in which case continuous fastener elements (14) are to be attached thereto. Alternatively, a swollen core portion (13) may be formed on the surface of the fastener-element-mounting portion (10), in which case single-type separate fastener elements are to be attached thereto. As a flexible yarn (6), a finished yarn (7) having a bulk and produced by textured processing multifilament yarn is used so that mounting of the fastener elements are facilitated and the configuration of the fastener tape (1) is stabilized. Therefore, a fashionable fastener tape formed of transparent or semi-transparent woven fabric can be obtained.