31 results about "1-aminohydantoin" patented technology

A process for preparing 1-amino hydantoin artificial antigen belongs to the technical field of biochemical industry, which comprises using 1-amino hydantoin artificial antigen as raw material, reacting with p-aldehydobenzoic acid as stirring, synthesizing semi-antigen 1-amino hydantoin-p-aldehydobenzoic acid (CPAHD), coupling carboxyl on semi-antigen and amino on bovine serum albumin (BSA) through adopting carbodiimide method, thereby preparing artificial antigen. The invention synthesizes artificial antigen of 1-amino hydantoin, and the synthetic steps are simple and effective. The invention can be completely applied in immune analysis, provides a convenient method for further research, and can meet domestic research demands.

The invention relates to the field of pharmaceutical synthesis, in particular to a method for synthesizing thymalfasin, and aims to solve the technical problems of difficulty in separation and purification, low total yield and high production cost of a conventional method. According to the scheme, the method for synthesizing thymalfasin comprises the steps as follows: a, a polypeptide fragment 1 and a polypeptide fragment 2 provided with protecting groups on side chains are synthesized; b, a C terminal of the polypeptide fragment 1 and an N terminal of the polypeptide fragment 2 are coupled, and the protecting group at the N terminal is removed to obtain polypeptide resin I; c, according to an amino acid sequence of thymalfasin, amino acids from the eleventh to the first are sequentially coupled one by one according to the order from the C terminal to the N terminal, then the protecting group at the N terminal is removed, and acetylation is performed to obtain thymalfasin resin; and d, the thymalfasin resin is subjected to acidolysis to remove the C terminal resin and all protecting groups to obtain a coarse thymalfasin product, and thymalfasin is obtained after purification. With the adoption of the method, the product yield can be greatly improved, and the synthesis cycle is shortened.

Disclosed is a modified flavine-adenine-dinucleotide-dependent glucose dehydrogenase (FADGDH) having an improved thermal stability compared to a wild-type FADGDH, which is preferably derived from a eukaryote, more preferably derived from a filamentous fungus, still more preferably derived from a bacterium belonging to the genus Aspergillus. For example, the modified FADGDH has a primary structure having the substitution, deletion, insertion or addition of at least one amino acid residue in the amino acid sequence for FADGDH depicted in SEQ ID NO:2 or 46 in the Sequence Listing.

The invention relates to an organophosphorus pesticide degrading enzyme obtained by genetic engineering transformation. The organophosphorus pesticide degrading enzyme transformed by random mutation is generated by replacing an amino acid site of the organophosphorus pesticide degrading enzyme from pseudomonas stutzeri, and the replacing amino acid site is located at the 71st site. The organophosphorus pesticide degrading enzyme is excellent in degrading activity of chlorpyrifos and methyl to ethion and excellent in heat stability.

The invention relates to a method for producing large-grained nitrofurantoin crystals, and belongs to the field of chemical synthesis. The invention adopts a technical proposal which comprises: placing a crude product of nitrofurantoin formed by the condensation of raw materials of 5-nitrofurfural diacetate and 1-aminohydantoin, and DMF of which the weight is two times of that of the crude product of the nitrofurantion in a retort, heating the mixture to between 85 and 90 DEG C, stirring the mixture, maintaining the temperature for 10 minutes, stirring the mixture, opening a clamping sleeve, cooling the retort by cooling water for 80 to 90 minutes to between 30 and 35 DEG C, stopping stirring, standing the retort for 2.5 to 3 hours to less than 2 DEG C below zero, casting material, and washing the material with 95 percent ethanol to obtain odorless DMF. Nitrofurantoin crystals prepared by the process are larger and the granularity of 95 percent of the products is more than 80 meshes, so the process facilitates filtration and separation and contributes to the reduction of production cost.

The invention relates to an protein A domain Z derivative with a specific binding effect on an antibody and an application thereof. According to the invention, mutation of N23T and mutation of at least one amino acid residue are generated in a domain Z amino acid sequence. The derivative is obtained through a strategy of mutation of at least one amino acid residue in Helix1 and 2 in an protein A mutation domain Z. In addition, the invention also provides a preparation method for an affinity chromatography matrix by utilizing the domain Z derivative as a ligand. Compared with the affinity chromatography matrix by utilizing the domain Z derivative as the ligand, the domain Z derivative provided by the invention has higher chemical stability, and has a protein denaturation temperature in alkaline solution increased by 4 DEG C; and the synthesized affinity chromatography matrix maintains considerable antibody adsorption capacity.

A substitution mutation that improves polymerization activity of a polyhydroxyalkanoic acid synthase is identified. At least 1 amino acid residue selected from the group consisting of a histidine residue at position 17, a proline residue at position 71, a valine residue at position 131, a methionine residue at position 205, a leucine residue at position 230, and a proline residue at position 239 of a polyhydroxyalkanoic acid synthase derived from Alcanivorax borkumensis is subjected to substitution mutation with another amino acid.

The invention discloses a chemically synthesized HSV1 virus gD glycoprotein extracellular region gene fragment and expression and an application thereof, and relates to the fields of genetic engineering technology, vaccine and diagnostic reagent. By computer analysis, the invention screens out the HSV1 virus gD glycoprotein extracellular region fragment containing strong antigen epitope, totally 284 amino acids, namely from the 1st to the 284th; codons which are preferred by both eukaryon and pronucleus organism are selected; and a brand new gene sequence of the antigen epitope is chemically synthesized; the genetic engineering technology is utilized to express the gene fragment and prepare the strong antigen epitope fragment and antiserum of the HSV1 virus gD glycoprotein. The expressed HSV1 virus gD glycoprotein can be applicable to the detection of vaccine, HSV1 virus antibody or antigen and immune preparation of HSV1 virus monoclonal antibody and polyclonal antibody and the like.

The invention discloses a synthesis method of thymalfasin. The synthesis method comprises the following steps: a, synthesizing a polypeptide segment 1 and a polypeptide segment 2, which have protecting groups on side chains; b, coupling a C end of the polypeptide segment 1 and an N end of the polypeptide segment 2; then removing the protecting group of the N end to obtain polypeptide resin I; c, sequentially coupling the eleventh to the first amino acids one by one according to the sequence from the C end to the N end and removing the protecting group of the N end; then carrying out acetylation to obtain thymalfasin resin; d, removing the resin of the C end and all the protecting groups from the thymalfasin resin to obtain a thymalfasin crude product; purifying to obtain the thymalfasin. By adopting the method disclosed by the invention, the yield of the product can be greatly improved and the synthesis period is shortened.

The invention discloses a chemosynthetic HSV2 virus gD glycoprotein extracellular region gene segment as well as expression and application thereof, which relates to the technical field of gene engineering and the fields of vaccines and diagnosing agents. In the invention, through computer analysis, an HSV2 virus gD glycoprotein extracellular region segment containing strong antigen epitope is screened, and the HSV2 virus gD glycoprotein extracellular region segment contains 286 amino acid from the 1st amino acid to the 286th amino acid, and codons favored by both eucaryon and procaryote are selected to chemically synthesize a new gene sequence with the strong antigen epitope. Therefore, the gene segment is expressed by using the gene engineering technology, and the strong antigen epitope segment of HSV2 virus gD glycoprotein and antiserum of the HSV2 virus gD glycoprotein are prepared. The expressed HSV2 virus gD glycoprotein can be used for detecting vaccines, HSV2 virus antibody or antigen and preparing anti-HSV2 virus mono-antibody, poly-antibody and the like for immunity.

The invention relates to a G protein competitive inhibitory peptide, which starts from a 55 peptide sequence and obtains a series of derived polypeptides by deleting amino acid residues in any number more than one in any point from the first amino acid residue at the amino end and at least remaining twelve amino acid residues at the amino end. The length of the polypeptide is shortened up to 78.2 percent; and the polypeptide has a remarkable effect on anti-myocardial remodelling. The invention also relates to a method for preparing the series of derived polypeptides, which successfully synthesizes a target polypeptide with the purity up to 99.2 percent by utilizing advanced peptide synthesis technology. The invention further relates to the preparations containing the polypeptides and the application thereof in the preparation of an anti-myocardial remodelling medicament.

The invention discloses a detection method for 1-aminohydantoin hydrochloride in animal tissues and a detection card. The detection card and a reagent are provided, wherein the surface of the detection card is provided with a colloidal gold test strip; the inner side of an ELIASA hole is provided with a monoclonal colloid gold marker antibody of frozen 1-aminohydantoin hydrochloride; the top of the surface of the detection card is provided with comparison color blocks at equal intervals; the reagent comprises deionized water, 1M hydrochloric acid, a derivatization reagent, an extraction agent, 1M sodium hydroxide, gold chloride, double distilled water, a chloroauric acid solution, a 1-percent sodium citrate aqueous solution, 0.1mol/L K2CO2 and a 0.1mol/L HCL cloning solution. In the detection method, the monoclonal colloid gold marker antibody is used, so that covalent bonds between gold particles and antibody molecules are avoided in the monoclonal colloid gold marker antibody, and the metal particles and the antibody molecules are combined through Van der Waals force among charges of different polarities; the colloid gold marker has very small influences on the specificity and affinity of the antibody, so that the detection accuracy of the 1-aminohydantoin hydrochloride can be increased.

The invention discloses a monoclonal antibody NP11-4 chimeric Fab antibody against schistosoma japonicum, a preparation method and the application thereof, which relates to genetic engineering technology and the field of preparing therapeutic drugs for schistosomiasis. The application is located on the monoclonal antibody NP11-4 of surface membrane of adult worms, cercaria membrane, schistosomulum membrane, egg shell and miracidium membrane of the schistosoma japonicum; genetic engineering technology is used for extracting the total RNA of a hybrid tumor cell strain; an RT-PCR method is used for amplifying VH and VL genes; PCR is used for respectively amplifying the Fd and the total length L of murine VH, VL and human CH1 of IgG1, CL, and then the chimeric Fab gene is amplified by overlapping and extending PCR and using Fd and L genes as templates; the chimeric Fab gene is restricted enzyme and connected with a carrier pComb3XSS and cloned to colon bacillus Top10F', and then an interest protein is induced to acquire soluble expression. At the N end of the expressed monoclonal antibody NP11-4 chimeric Fab antibody against schistosoma japonicum, the part from the first amino acid to the 215th amino acid is the L chain of the chimeric Fab antibody, and the part from the 216th amino acid to the 488th amino acid is the Fd section of the chimeric Fab antibody, the L chain and the Fd section are connected through a disulfide linkage, and the chimeric Fab antibody has an overall length of 488 amino acids.

The present invention refers to proteins and bioactive peptides with immunomodulating and antiviral activity. Present peptide complexes have three-dimensional structure and are described by the following structural formula (SEQ ID NO: 23):

where: X₁ is absent or contains not less than 1 amino acid; R1 and R2 peptide chains, containing amino acid residues, His or Cys, interactable with transition metal ions, with R1 containing up to 5 amino acid residues or absent; R2 contains up to 3 amino acid residues or absent. Histidine-rich peptide complexes, primarily alloferon family peptides with Zn ions, will make it possible to create drugs with targeted mechanism of action, and design them with regard to understanding of drug target structure.