75 results about "Glutamine aminotransferase" patented technology

The invention discloses a method for improving gel property of minced fish product through adding glutamine aminotransferase which comprises, adding into minced fish processed from fresh fish as raw material complex addition agent consisting soybean protein, polyphosphates and glutamine aminotransferase, adding addition agent, then kneading the minced fish 10-20 minutes, the gel property of the obtained minced fish product is increased to 400-500g from the previous 200g before addition.

The invention discloses a mutant of glutamine transaminase expressed by an active form, and belongs to the field of gene engineering and fermentation engineering. A genetically engineered bacterium po1h/hpro-mTG of high-output glutamine transaminase is structured by using yarrowia lipolytica as a host. The bacterial strain is high in enzyme production level; the fermenting enzyme activity of a shake flask is up to 11.7 U/mL, and improved by 106 times in comparison to that before transformation; the fermenting enzyme activity of a fermenting tank is up to 43.7 U/mL. Through co-expressing proteases TAMEP and hpro-mTG, the activity expression of glutamine transaminase is realized; the fermenting enzyme activity of the shake flask can reach 6.7U/mL, and the fermenting enzyme activity of the fermenting tank can reach 21.4U/mL. The fermenting enzyme production level of the recombinant bacteria is high, the production cost of the glutamine transaminase is reduced; the mutant is good for the industrial production of the glutamine transaminase.

The invention discloses a glutamine transaminase with improved heat stability and application thereof. High-efficiency expression of microbial transglutaminase (MTG) in escherichia coli serves as a modification platform, a label facilitating improvement of heat stability is added at the C end of MTG maturase, preference is given to IGCIILT to obtain a mutant strain with good enzymatic property, and the heat stability is improved by 2.5 times and 3 times. Modified enzyme is suitable for industrial application, the production cost can be reduced, and the production efficiency can be improved.

The invention discloses gluten protein colloid granules and a preparation method and application of the gluten protein colloid granules. The preparation method comprises the following steps: gluten protein is subjected to crosslinking reaction under the effect of glutamine transaminase so as to form gluten protein colloid granules; micro hydrophilic molecules with primary amine groups are added into the reaction system, and are at least one of L-lysine, glucosamine and L-glutamic acid, and the mass ratio of micro hydrophilic molecules with primary amine groups to the gluten protein is 1 to (10-100). According to the invention, the micro hydrophilic molecules with primary amine groups are added into the reaction system; the gluten protein is subjected to crosslinking among molecules and within molecules, and crosslinking reaction is performed together with the micro hydrophilic molecules with primary amine groups; on one hand, glutamine or asparaginate in the gluten protein can be prevented from being subjected to deamidation reaction by glutamine transaminase, and on the other hand, because the micro hydrophilic molecules with the primary amine groups contains electrified groups, relatively high surface electric charge is given to the gluten protein.

The invention discloses a method that is used for finishing wool fabrics by catalyzing a foreign protein through a transglutaminase and belongs to the filed of biotechnological application. The method implements proper chemical or protease preprocessing on wools, grafts and coats a gelatinum of the foreign protein or a caseinum on the surface of wool fibers under the catalysis of the transglutaminase, endues the wool fabrics with certain felt-proof property, and improves the physical and mechanical performance of the wool fabrics to a certain degree. Compared with the traditional felt-proof finishing methods of the wools, the method that is used for finishing the wool fabrics by catalyzing the foreign protein through the transglutaminase replaces traditional chemical finishing agents with bio-enzyme and biomacromolecule, has less fiber strength loss and is easier to control by comparing with pure protease processing, leads the biological modification of the wools to be possible, greatly lowers environmental pollution, reduces COD in discharged water and improves ecological environment; simultaneously the method has gentle action condition, avoids high-temperature baking, saves energy and improves the quality of fabric products.

The invention discloses a glutamine transaminase high-yielding strain and application thereof. The strain is named as streptomyces hygroscopicus NYU-70 according to classification and naming, and has been preserved in China Center for Type Culture Collection and preservation number of CCTCCM2014121. Streptomyces hygroscopicus NY-1 is used as a starting strain for low energy ion implantation mutagenesis, activity of the enzyme of the strain after mutagenesis is measured through casein gel method and colorimetric method, mutant strains with high activity in producing glutamine transaminase are screened out as the starting strains for the next round of mutagenesis, and the above steps are repeated to obtain the glutamine transaminase high-yielding strain. The strain has high activity and good genetic stability in fermentation production of glutamine transaminase. The mutant strain can be used in liquid shake flask fermentation to obtain glutamine transaminase, and has enzyme activity of 16.9U / mL.

The invention discloses a separation and purification method of new microbial transglutaminase. The method comprises the following steps of carrying out alcohol precipitation on new streptomyces mobaraensis fermentation liquor with the strain number being CGMCC No.10804 obtained through natural screening, carrying out anion exchange chromatography, desalting, freezing and drying to obtain the microbial transglutaminase. The obtained transglutaminase has the purity being larger than or equal to 90 percent, the plasma endotoxin level being less than or equal to 0.02EU/mL, the specific enzyme activity being 25 to 30U/mg, and the recovery rate being larger than or equal to 70 percent. The separation and purification method of the new microbial transglutaminase is simple in process, low in cost, and high in enzyme recovery; the obtained transglutaminase is high in purity; the microbial transglutaminase obtained through fermenting the strain is stable in property, so that the industrial production is convenient; a feasible method is provided for satisfying medical grade MTGase scale production.

The invention discloses an immobilized glutamine transaminase preparation method. The method includes that natural macromolecular compounds such as sephadex, agarose gel, carrageenan and gelatin are adopted for enzyme immobilization, an immobilized embedded substance is immersed into a liquid mixture of alcohols, carbohydrates, an antioxidant and the like, and accordingly stability of an immobilized enzyme preparation is greatly improved. The immobilized glutamine transaminase preparation method has advantages that preservation time of glutamine transaminase at a low temperature, the normal temperature and a high temperature is greatly prolonged, and stability of glutamine transaminase is remarkably improved.

The present invention relates to a kind of bean curd as well as its preparing method. The present invention provides a bean curd, which is characterized in that the bean curd contains glutamine aminotransferase. The present invention also provides a method for preparing the bean curd. The bean curd has the characteristics of traditional bean curd that taste lubricating and candour exquisite, also has the hardness and elasticity of the traditional bean curd, which ensures the bean curd obtain unprecedented taste and texture.

The invention belongs to the technical field of bioengineering and particularly relates to transglutaminase mutants as well as genes, engineering bacteria and a preparation method thereof. The mutantsare obtained from target genes through mutation with a sequential error-prone PCR method and screening, specific enzyme activity of the mutants expressed in a Bacillus subtillis expression system isincreased by 19% and 27% respectively compared with that of wild type transglutaminase, and the application prospect is broad.

The invention provides a process for extending quality period of high-grade meat products, which comprises spraying glutamine aminotransferase solution containing 50-250 active units of glutamine aminotransferase in each 100g of the solution, or drenching the meat into the prepared solution.

The invention provides a mutagenic Lactobacillus casei strain and a biological preparation thereof. The mutant strain is Lactobacillus casei strain KJY14(KJY-HN001-01-04), CGMCC No.15424, deposited onMarch 7, 2018. The invention also provides a biological preparation containing Glutamine transaminase prepared by the mutagenic bacterium. The invention also provides the use of the mutant strain alone or in combination with other lactic acid bacteria for preparing coagulant for soy yoghurt, yoghurt tofu, soybean albumen beverage and soybean albumen acid soup.

The invention relates to a glutamine transaminase production bacterium which is obtained by mutagenesis screening and preserved in China Center for Type Culture Collection, wherein the preservation No. is CCTCC NO:M 2020194, CCTCC NO:M 2020195, CCTCC NO:M 2020196 or CCTCC NO:M 2020197. Compared with the glutamine transaminase of an original strain, the glutamine transaminase production bacterium disclosed by the invention has the advantages that the yield of the glutamine transaminase production bacterium is increased by at least 3.5 times, the enzyme activity of fermentation liquid can achieve 33U/mL or above, and the industrial application prospect is broad.

The invention relates to a food taking powdered milk and white sugar as main ingredients, that is, novel milk custard, and a preparation method thereof. The invention is characterized in that: the provided novel milk custard contains no egg white and renninum, or glutamine aminotransferase and has rich nutrition, good taste and health care function. The novel milk custard is mainly prepared with the following raw materials by weight proportion: 35-70 parts of powdered milk, 15-50 parts of white sugar, 1.0-2.5 parts of calcium carbonate, 0.5-2.5 parts of compound carrageenan, 0.5-2.5 parts of glucomannan and 1-10 parts of other materials. Compound carrageenan and glucomannan are both gelling agents which belong to dietary fiber and have health care function; the preparation method of the invention is as follows: the raw materials are evenly blended, added with 4-5 times of warm water by weight proportion, and then heated to 80-90 DEG C, and the temperature is kept for 10-30 minutes; filling, cooling, standing still and consolidation forming are carried out to obtain the edible milk custard. The novel milk custard has the advantages of no bitter flavor, good mouthfeel, rich nutrition and health care function, and the preparation method can facilitate large-scale production and the improvement of production efficiency.

The invention discloses a preparation method of convenient instant bird's nest and a product thereof. The method comprises the following steps: pretreating bird's nest; adding into a glutamine transaminase water solution for soaking; draining the material, immersing the drained bird's nest shreds into water; and adding acid to adjust the pH value of the system to 0-5, soaking at 30-100 DEG C for 20-600 minutes, draining the material, cleaning with clean water at normal temperature, fishing out the bird's nest shreds, draining, drying, mixing with water or sweet water, sub-packaging, sealing, sterilizing in a high-temperature pressure cooker, cooling, inspecting and packaging to obtain the convenient instant bird's nest. After the bird's nest shreds are treated by glutamine transaminase, the bird's nest shreds are subjected to enzymolysis; the protein denaturation further enables the internal structure of the bird's nest shreds to be more compact, and the protein denaturation and the bird's nest shreds have a synergistic effect, so that the thermal stability during high-temperature sterilization is improved, the bird's nest shreds are insoluble during high-temperature sterilizationand later storage, and the phenomenon of water melting of the bird's nest shreds is avoided.

The invention belongs to the field of seasonings, and discloses a composite preparation method of chicken powder based on a low-salt fermentation process, which comprises the following steps: mincingchicken, killing miscellaneous enzymes, carrying out enzymolysis, and carrying out post-treatment after enzymolysis. Wherein the specific enzymolysis process comprises the following steps: step 1, adding a compound enzyme into the minced chicken subjected to impurity enzyme deactivation, wherein the compound enzyme consists of protease and glutamine transaminase, the enzymolysis temperature is 50+/-2 DEG C, and the enzymolysis time is 2-2.5 hours; and step 2, after the step 1 is finished, adding papain into a mixture, wherein the temperature is increased to 65 +/-2 DEG C, and the enzymolysistime is 0.8-1.2 h; wherein the weight ratio of the protease to the glutamine transaminase to the papain is 7: (1.4 to 1.6) : (1.5 to 1.7); wherein the protease, the glutamine transaminase and the papain account for 1.9-2.1% of the total weight of the chicken. The method is short in fermentation time and high in product yield, and meanwhile, the invention further provides chicken powder.

The invention discloses a preparation method for a transglutaminase liquid enzyme activity stable preparation. The preparation method includes the following steps: step 1) a step of enzyme powder dissolution, namely the step of mixing transglutaminase powder and water, dissolving and performing centrifugation to take supernatant; step 2) a step of degerming, namely the step of adopting a film of 0.22 [mu]m to filter a degerming enzyme liquid and a reagent; and step 3) a step of mixing, namely the step of quantitatively measuring or weighing an enzyme liquid, a water activity regulator and a redox potential agent, performing mixing, using a pH conditioning agent to supplement 100% volume, and performing uniform mixing so that the transglutaminase liquid enzyme activity stable preparation can be obtained. The stability of the enzyme activity of a transglutaminase liquid enzyme in the preparation prepared by the method can be enhanced, and the corruption of microorganisms cannot occur; and the technical problems in the prior art that the enzyme activity of the transglutaminase liquid enzyme is hard to preserve for a long time can be solved, so that the preparation method can have wideapplication prospects.

The invention discloses a method for improving the morphological condition of animal cell-derived artificial meat, and belongs to the technical field of food engineering. Meat paste obtained by culturing animal stem cells in different parts by weight, salt, phosphate, water, casein meal and glutamine transaminase are mixed. Meanwhile, the invention provides a treatment method for a finished product of animal cell culture. The glutamine transaminase is added to promote large-scale crosslinking of the animal cells, a reaction condition is provided by a mixture of the phosphate, the salt and thewater, and a bridge is provided for adhesion of the glutamine transaminase by adding casein, so that the crosslinking degree is deepened. The artificial meat treated with the method has high compactness and good taste.

The invention discloses a method for continuously extracting glutamine transaminase from fermentation liquor, and belongs to the field of bioengineering. The method comprises the following steps: introducing sterile compressed air into a fermentation tank after fermentation is ended; leading out the fermentation liquor to ceramic composite membrane equipment from the fermentation tank, feeding the fermentation liquor from which thallus and impurities are removed into membrane separation equipment, and carrying out ultra-filtration concentration; connecting all the equipment by a pipeline with a flow control valve; continuously running after setting parameters in absence of people involvement; adding auxiliary materials to the fermentation liquor after concentrating, and then sequentially carrying out solvent participation and centrifugal separation; and adding auxiliary materials again and drying in vacuum, so as to obtain glutamine transaminase powder. The method has the advantages of being reasonable and continuous in process, simple in equipment, simple and convenient to operate, low in cost, and easy to industrially amplify. By adopting the method, the technical problem that the steps such as salt precipitation, dialysis, ion exchange column separation and the like in traditional extraction are not needed, resulting in easy industrial application is solved.

The invention relates to a gene sequence optimized glutamine transaminase as well as a secretory expression method and application thereof. A streptomyces mobaraense-derived glutamine transaminase gene and a leader sequence thereof are reformed according to optimal codons of pichia pastorris to obtain an optimized glutamine transaminase gene and an optimized leader sequence thereof. A recombinant pichia pastoris system co-expressed by the optimized glutamine transaminase gene and the optimized leader sequence thereof is constructed, and a strain of high-expression recombinant glutamine transaminase is obtained by screening. The optimized glutamine transaminase gene and the optimized leader sequence thereof can be stably and efficiently expressed in the pichia pastoris, the activity of the expressed recombinant glutamine transaminase is up to 0.5 U/mL and is 4 times that of the original glutamine transaminase, and a foundation is laid for further industrial expanded production of the glutamine transaminase.

The invention discloses a glutamine transaminase separation and purification method which comprises the following steps: coating preserved Bacillus subtilis in a NA slant culture medium, culturing, centrifugating, discarding the supernate, washing the obtained bacterium with a pH-7.0 phosphoric acid buffer solution, and preparing a bacterium suspension; carrying out microwave treatment on the bacterium suspension, inoculating in a seed culture medium, inoculating the bacterium into a fermentation culture medium according to the inoculum size of 5%, culturing for some time, carrying out ultrasonic treatment, putting in a water bath shaking table, and culturing for 48 hours to obtain a fermentation culture fluid; and centrifugating the fermentation culture fluid, filtering through a microfiltration membrane, collecting the enzyme solution, and carrying out freeze-drying to obtain the glutamine transaminase. The phytase is added into the soybean protein extracting solution to cut off the phytic acid connecteed between the soybean 7S globulin and soybean 11S globulin; the whole separation process is carried out under normal temperature conditions, thereby avoiding the problem of longer globulin separation process time caused by the addition of the reducer; and the separated soybean 11S globulin and soybean 7S globulin have higher yield and purity.

The invention discloses a preparation method of cross-linking enzyme. The preparation method comprises the following steps: mixing polyphenol oxidase with a glutamine transaminase solution for a reaction; the cross-linked enzyme microparticles with a particle size of several micrometers to tens of micrometers and different vigor sizes can be obtained,the cross-linked glutamine transaminase prepared by the method can be separated from a solution by means of filtration, centrifugation and the like, and the prepared cross-linked glutamine transaminase is used for polyethylene glycol (PEG) modification and the like of protein drug molecules. The cross-linked glutamine transaminase is easy to recover and can be repeatedly used in the use process, no burden is caused to product separation, and the production cost is greatly reduced. According to the method, the crosslinking process is environmentally friendly, mild and efficient, the reaction is controllable, a carrier is not needed, glutamine transaminase does not need to be purified, and multiple enzymes can be crosslinked and immobilized together.

The invention provides a peptide chain label with specific amino acids for realizing protein separation and purification. The invention also provides a water-soluble high-molecular polymer which has aglutamine unit structure in the molecule. The invention further provides a protein separation and purification method based on amino acid specific recognition, wherein escherichia coli is used as a host cell to express protein with the specific amino acid peptide chain label; glutamine transaminase has a function of specifically identifying and crosslinking a primary amine group of lysine and anamide group of glutamine, so that the protein with the peptide chain label and the water-soluble polymer are specifically identified and crosslinked to form a conjugate; and the specific sequence is recognized and cut by thrombin, so that the conjugate is cut, and the protein is separated and purified. A method for specifically identifying amino acids by using the glutamine transaminase and thrombin provided by the invention provides a basis for the aspects of protein purification, separation and the like, and has a wide application prospect.