10 results about "Carbohydrate chains" patented technology

The invention belongs to the technical field of biological detection, and particularly relates to a method for analyzing and detecting IgG N-glycan in dried blood spots. The dried blood spot sample is adopted to replace a traditional serum sample, so that the technical problem of IgG N-carbohydrate chain degradation under the normal-temperature storage condition of the serum sample is effectively solved, and the stability of the sample and the reliability of a detection result are remarkably improved. The dried blood spot sample collecting method is simple and convenient, vein blood sampling is not needed, the method is suitable for large-scale screening and application of special crowds, and the clinical application range of IgG N-glycan analysis is widened. Besides, the dried blood spot sample can be stored for a long time at room temperature, the transportation and storage cost is reduced, meanwhile, analysis can be completed only through a trace amount of blood, the method is suitable for repeated sampling and long-term monitoring, and a technical support is provided for research and application of IgG glycosylation as a biomarker.

The invention provides a preparation method of an antibody conjugate containing an sLeX tetrasaccharide structure, which comprises the following steps: S1, sequentially adding Endo S2 enzyme and alpha-L-fucosidase into a target antibody, and respectively analyzing glycosylation to avoid modification site conflict or carbohydrate chain structure interference; s2, adding the accurately represented antibody in the S1, B4GalT1 and UDP-Gal into a Tris-HCl system containing Mn < 2 + >, and incubating to obtain a reaction solution I; s3, the reaction liquid I, ST3Gal3, CMP-Neu5Ac and Tris-HCl containing Mg < 2 + > are taken and mixed, and incubation is carried out; adding CMP-N-acyl neuraminic acid phosphodiesterase for reaction, and purifying Protein A to obtain a purified antibody I; s4, the purified antibody I, alpha1, 3 FucT-2HR, GDP-Fuc and Tris-HCl containing Mg < 2 + > are taken and mixed, and incubation is performed; and purifying Protein A to obtain a target product. According to the modified antibody obtained by the invention, while the targeting property is improved, the binding affinity of the antibody and a tumor cell surface antigen can be enhanced, so that the immune blocking activity of the antibody is further enhanced, and dual improvement of the targeting property and the activity is realized.

The invention relates to the technical field of biomedical detection and data processing, and discloses an esophageal cancer risk assessment system and method based on a serum N-glycosylation spectrum.The system obtains multi-dimensional detection data containing a collision sectional area, distinguishes N carbohydrate chain isomers by means of the data and generates original feature vectors; the method comprises the following steps: calculating a step-by-step truncation ratio of key enzyme nodes according to N sugar chain biosynthesis network topology, and constructing a dynamic enzyme effect feature vector; carrying out individualized correction on an esophageal tumor basic template by utilizing the vector, carrying out deconvolution on an original signal into a hepatogenic background and an esophageal tumor source signal through a non-negative least square method, and calculating an esophageal tumor leakage coefficient representing a tumor contribution degree; and finally, carrying out weighted fusion on the leakage coefficient and the risk-associated enzyme feature to judge the risk level. By analyzing enzymatic kinetics and separating trace tumor signals, isomer overlapping and background interference are overcome, and evaluation sensitivity is improved.

Disclosed are compositions and formulations for removing dental calculus which comprise enzymes or other biocatalysts which cleave (i) surface-accessible nucleic acid polymers and (ii) glycoprotein carbohydrate chains at galactose residues. Optionally, one or more proteolytic enzymes are included. The compositions destroy the structural integrity of the calculus, allowing it to be readily removed without requiring special treatment by a trained dental professional. Also disclosed are methods for removing dental calculus using the disclosed compositions and formulations.

The utility model relates to the field of teaching aids, in particular to a cell membrane inlaid flowing three-dimensional dynamic model, which comprises a phospholipid bilayer model, at least one carbohydrate chain module, at least one movable membrane protein molecule module and at least one ion module, the phospholipid bilayer model comprises a phospholipid molecule upper layer model composed of a phospholipid molecule head module and a phospholipid molecule tail module, and a phospholipid molecule lower layer model composed of a phospholipid molecule head module and a phospholipid molecule tail module. Meanwhile, a penetrating type membrane protein molecule module, a semi-embedded type membrane protein molecule module, a full-embedded type membrane protein molecule module and a floating type membrane protein molecule module are further arranged on the phospholipid bilayer model. The three-dimensional model for dynamically displaying the cell membrane fluidity and the types, functions and motion modes of the membrane proteins improves the teaching effect of related knowledge of the cell membranes, and meanwhile, the model is detachable, easy to assemble and convenient to store and transport.

The invention discloses a sphingolipid ceramide N-deacylase mutant. The mutant is formed by amino acid mutation in sphingolipid ceramide N-deacylase as shown in SEQ ID NO.1, and the amino acid mutation is selected from one or more of mutation of the 232 site Tyr, mutation of the 254 site Asn, mutation of the 416 site Phe and mutation of the 592 site Leu. The invention also discloses application of the mutant in preparation of ganglioside derivative molecules by efficient enzymatic synthesis. The stability of the sphingolipid ceramide N-deacylase SCDase mutant is improved, and the pyrolysis chain temperature Tm of the mutant is improved by 5.79 DEG C compared with that of a wild type; the sphingolipid ceramide N-deacylase SCDase mutant provided by the invention enhances the enzyme preparation efficiency of ganglioside, especially for short-chain fatty acids (carbohydrate chain length lt; and 4) the synthetic activity is improved by more than two times, and the result broadens the practical application value of the SCDase enzyme.

Compositions and formulations for removing dental calculi are disclosed comprising an enzyme or other biocatalyst that cleaves (i) a surface accessible nucleic acid polymer and (ii) a glycoprotein carbohydrate chain at galactose residues. Optionally, one or more proteolytic enzymes are included. The composition disrupts the structural integrity of the stone so that it is easy to remove without the need for special treatment by a training primordial dental professional. Also disclosed are methods for removing dental calculi using the disclosed compositions and formulations.

The invention discloses a magnetic hydrothermal carbon material reversely wrapped by an unmarked cell membrane as well as a preparation method and application of the magnetic hydrothermal carbon material, magnetic carbon nanospheres are prepared by a hydrothermal method, and then carboxyl groups on the surfaces of the magnetic carbon nanospheres and residual amino groups of lectin such as concanavalin A are subjected to amide condensation, so that lectinized hydrothermal magnetic carbon nanospheres are obtained. Finally, agglutination reaction can be carried out on agglutinin and carbohydrate chains on the outer surface of the cell membrane, so that the cell membrane is wrapped from inside to outside. The biomimetic material can screen drugs acting on the inner side of a cell membrane, does not need to label the cell membrane, can reduce damage to membrane protein, provides a new technical means for deeply exploring lead compounds in natural products, and promotes development of traditional Chinese medicine anti-osteoporosis drugs. According to the invention, two novel potential anti-osteoporosis components targeting the inner surface of an osteoblast cell membrane in herba epimedii are successfully found.

Provided are methods of synthesizing glycolipids. The methods combine chemical and enzymatic transformations to rapidly provide diverse natural and functionalized glycolipids in a high convergent matter. Stepwise enzymatic elongation of a carbohydrate chain of a common glycolipid precursor, compound (1), provides glycan intermediates of Formula (II), using sugar-nucleotides as glycosyl donors and glycosyltransferases as enzymes. Also provided are glycan intermediates of Formula (II) and alkene intermediates of Formula (IV) and methods of preparing same.

The present invention, in the field of bioengineering and biotechnology, relates to a method for preparing a recombinant antibody with a unique glycan profile produced by a genome-edited CHO host cell. Specifically, according to a method of the present invention, the TALEN technology is used to edit the FUT8 gene in CHO cells that have been adapted for serum-free suspension growth. The edited CHO host cells can produce recombinant antibodies with a unique glycan profile. The unique glycan profile can be characterized by non-fucosylated N-linked oligosaccharide chains of the antibodies, extremely low N-glycosylation heterogeneity and uniform carbohydrate chains. The antibody prepared by the method of the invention exhibit significantly increased ADCC and greater stability.