6 results about "Microbial transglutaminase" patented technology

The invention discloses starch-collagen composite hydrogel as well as a preparation method and application thereof. Collagen is catalyzed by microbial transglutaminase to form a covalent cross-linked network, and meanwhile, hydroxypropyl starch is introduced to construct a physical interpenetrating network through molecular chain penetration and hydrogen-bond interaction; and chondroitin sulfate is further integrated to strengthen the network structure and biological activity through electrostatic interaction. The method is mild in condition and does not need a toxic chemical cross-linking agent, the obtained composite hydrogel has an interpenetrating double-network structure and has excellent mechanical properties, enzymatic degradation resistance and cell affinity, the compression modulus of the composite hydrogel is remarkably improved, the composite hydrogel can keep structural stability for a long time in a collagenase environment, cell adhesion and proliferation can be effectively promoted, and the composite hydrogel has a good application prospect. The hydrogel can be widely applied to tissue engineering scaffolds, wound dressings, drug sustained-release carriers and cartilage repair materials.

The invention belongs to the field of marine food processing, and provides a marine food containing yellow croaker and a preparation method thereof.The marine food containing yellow croaker is prepared by adopting collaborative design of a minced yellow croaker protein-polysaccharide composite nano colloid powder intermediate and low-molecular fish collagen, through microbial transglutaminase cross-linking and cryoprotectant compounding regulation and control, and the marine food containing yellow croaker and the preparation method of the marine food containing yellow croaker are obtained. A minced fillet protein continuous phase network structure with uniformly dispersed nano-particles is constructed, the gel strength is 900-1300 g.cm, the gel strength retention rate is not lower than 80% after 6 times of freezing and thawing cycles are frozen for 3-5 times, the unfreezing drip loss is not higher than 8 wt%, the hardness is 1500-2500 g, and the taste characteristics of high strength and good elasticity are obtained. The technical problems that high gel strength and freeze-thaw stability of a traditional surimi product are difficult to consider, the taste is worse easily due to improvement of mechanical properties, nano-particles are difficult to uniformly disperse in a high-solid-content system and the like are solved, and the surimi product has wide application value in the fields of surimi products, quick-frozen prepared foods and marine functional foods.

This application relates to site-specific conjugation of antibody lysine residues using solid phase immobilized microbial transglutaminase MTG and MTG in solution. Site-specific modification of proteins using microbial transglutaminase (MTG) is a powerful and versatile strategy for controlled modification of proteins under physiological conditions. We present evidence that solid phase microbead immobilization can be used to site-specifically and efficiently link different functional molecules important for further downstream applications to therapeutically relevant proteins, including scFV, Fab fragments and antibodies. We demonstrate that MTG remains firmly immobilized and there is no detectable column bleed and the enzyme activity is maintained during continuous operation, which allows for convenient recycling of the enzyme, thus outperforming solution phase MTG conjugation. Furthermore, it is shown that immobilized MTG exhibits an enhanced selectivity for certain residues in the presence of several reactive residues, all of which are targeted if conjugation is performed in solution. Site-specific lysine conjugation of antibodies using immobilized and solution MTG with a highly efficient glutamine-containing peptide is also reported. In addition, the generation of bis-site-specific conjugated IgGl with site-specific conjugation of both glutamine and lysine residues of an IgGl antibody using immobilized and solution MTG is reported. Site-specific glutamine conjugation with small peptides containing lysine residues and functional moieties is also described.

This invention belongs to the field of biomedical materials, and particularly relates to a hydrogel for cartilage repair and its preparation method. The preparation method of the hydrogel includes the following steps: (1) adding cross-linked modified chitosan and 8-O-acetylganoside methyl ester to a collagen solution, adjusting the pH to obtain a collagen polysaccharide solution; (2) adding metal ion microspheres to the collagen polysaccharide solution of step (1), stirring and reacting, then adding microbial transglutaminase for heating and reacting, adjusting the pH to obtain a mixed solution; (3) adding 1,4-butanediol diglycidyl ether and growth factors to the mixed solution of step (2), adjusting the pH, water bath, and dialysis to obtain the hydrogel. This preparation method is simple, and the obtained hydrogel has excellent mechanical strength and adhesion properties.

The application belongs to the field of biomedical materials, and particularly relates to a hydrogel for cartilage repair and a preparation method thereof. The preparation method of the hydrogel comprises the following steps: (1) adding cross-linking modified chitosan and 8-O-acetylmagnol methyl ester into a collagen solution, adjusting pH to prepare a collagen polysaccharide solution; (2) adding metal ion microspheres into the collagen polysaccharide solution in step (1), stirring and reacting, then adding microbial transglutaminase for heating reaction, adjusting pH to prepare a mixed solution; and (3) adding 1,4-butanediol diglycidyl ether and growth factors into the mixed solution in step (2), adjusting pH, water-bathing and dialysis to prepare the hydrogel. The preparation method is simple in process, and the obtained hydrogel has excellent mechanical strength and adhesion.

The application relates to the technical field of biomaterials, and discloses a high-biocompatibility hydrogel based on enzyme catalysis cross-linking and a preparation method thereof, which comprises the following steps: mixing a polypeptide mother liquor containing a tyrosine residue, functional nanoparticle tyrosinase and an MES buffer solution to obtain precursor solution A; mixing gelatin, recombinant elastin and a phosphate buffered saline solution to obtain a polymer mother liquor, and adding microbial transglutaminase into the polymer mother liquor to obtain precursor solution B; and mixing and reacting the precursor solution A and the precursor solution B to obtain the high-biocompatibility hydrogel based on enzyme catalysis cross-linking. In the application, the interpenetrating network constructed by the tyrosinase and the microbial transglutaminase sequentially catalyzes a significant synergistic enhancement effect. In a hyperglycemic environment, a mesoporous silica nanoparticle built-in level connection system is automatically activated, realizing multiple effects of antibiosis, anti-inflammation and promotion of angiogenesis.