471 results about "Protein engineering" patented technology

The invention discloses a protein optimization design and screening method and device based on an artificial intelligence algorithm, and the method takes fungal luciferase as an example, and integrates multi-dimensional bioinformatics analysis and deep learning technology to realize efficient protein engineering transformation and optimization. The method comprises the following steps: firstly, identifying a binding domain of luciferase and fluorescein by utilizing an AI-driven molecular docking simulation method, and determining a key conservative site by combining literature, evolutionary analysis and structural prediction; then, generating a protein functional domain skeleton under the constraint of a fixed site by adopting a diffusion model, and performing protein sequence prediction by utilizing a graph neural network model; and finally, scoring and screening the generated sequences to obtain high-stability candidate variants. According to the method, a conservative site dynamic fusion strategy is innovatively constructed, a fixed region is optimized through logic of structure prediction, evolution site intersection priority and literature site union set expansion, the diversity and adaptability of a protein design sequence are met, and the efficiency bottleneck of a traditional scheme is broken through.

The invention belongs to the technical field of protein engineering, and discloses a Brazilian sweet protein mutant and application thereof. According to the invention, lysine is used for replacing aspartic acid at the 29th site of Brazilian sweet protein, and / or arginine is used for replacing glutamic acid at the 36th site, and / or alanine is used for replacing aspartic acid at the 50th site, amino acid mutation at the sites is carried out to construct a Brazilian sweet protein mutant, and the Brazilian sweet protein mutant is subjected to heterologous expression in pichia pastoris GS115, so that the Brazilian sweet protein mutant is obtained. And carrying out sweetness performance evaluation on the expressed Brazilian sweet protein mutant. The sweetness property of the double mutant Asp29Lys-Asp50Ala protein is improved by 240% compared with the sweetness property of the Brazilian sweet protein before mutation.

The invention belongs to the technical field of protein engineering and biology, and discloses a recombinant III-type humanized collagen, a coding gene thereof, a protein preparation, a preparation method of the protein preparation, application of the protein preparation and a skin care product. The amino acid sequence of the recombinant III type humanized collagen is as shown in SEQ ID NO. 1. According to the recombinant III type humanized collagen, the transdermal absorption efficiency is greatly improved, and meanwhile, the proliferation and migration capabilities of keratinocytes are also remarkably improved. The collagen is widely applied to the fields of medical cosmetic plastic surgery, cosmetics and the like, and has a good application prospect.

The invention provides cat serum albumin and application thereof, and relates to the technical field of protein engineering. According to the invention, mutation is carried out on the cat serum albumin for the first time to obtain a beneficial mutation site, so that the cat serum albumin mutant which can be highly expressed in a pichia pastoris system is obtained. In addition, the cat serum albumin mutant I31L also has the effect of treating ascites due to cirrhosis, and the treatment effect is obviously higher than that in the prior art. A new biological material is provided for application of the cat serum albumin, and a foundation is laid for genetic engineering modification of the cat serum albumin.

The invention provides a recombinant XVII type collagen and application thereof, and relates to the technical field of protein engineering. The novel recombinant human XVII type collagen is obtained by optimizing and screening collagen structural domain sequences of the human XVII type collagen and then combining the sequences. The recombinant human XVII type collagen is consistent with the corresponding part of the amino acid sequence of the human XVII type collagen, does not generate immunological rejection when being applied to a human body, and can be widely applied to the industries of surgical medical treatment and medical beauty. In addition, the recombinant human XVII type collagen is high in stability, and the problem of protein degradation in the process of expressing recombinant protein by pichia pastoris can be avoided. In addition, the recombinant human XVII type collagen also has the effects of high biological activity, high biological safety, promotion of cell proliferation and differentiation and promotion of hair growth, and can be applied to the field of cosmetics or medicines as a functional component.

The invention provides a micromolecular recombinant XVII type collagen as well as a preparation method and application thereof, and relates to the technical field of protein engineering. The novel recombinant human XVII type collagen is obtained by optimizing and screening a plurality of spiral region sequences such as a collagen structural domain, a C-terminal region and a middle region of the human XVII type collagen. The amino acid composition of the recombinant XVII type collagen is consistent with that of a natural collagen alpha1 chain, immunological rejection is not generated when the recombinant XVII type collagen is applied to a human body, the recombinant XVII type collagen can be widely applied to surgical medical treatment and medical beauty industries, the molecular weight of the collagen is small, efficient secretion soluble expression in eukaryotic host cells such as pichia pastoris can be achieved, and the recombinant XVII type collagen has a good application prospect. And industrial large-scale production is carried out. According to the present invention, the verification results show that the micromolecular recombinant XVII type collagen further has basement membrane anti-aging activity, wherein the basement membrane anti-aging activity specifically comprises the improvement of the expression levels of the IV type collagen, the VII type collagen and the XVII type collagen;

The present invention is related to the field of protein engineering technology which increases the enzymatic activity and thermal stability of human hyaluronidase which is an enzyme that hydrolyzes hyaluronic acid; and more particularly to hyaluronidase PH20 variants or fragments thereof, which comprise one or more amino acid residue substitutions in the region corresponding to the alpha-helix region and its linker region in the amino acid sequence of wild-type PH20 of SEQ ID NO: 1 and in which one or more amino acid residues at the N-terminus and / or the C-terminus are selectively cleaved additionally.Specifically, the present invention relates to PH20 variants or fragments thereof, which comprise one or more amino acid residue substitutions selected from the group consisting of T341A, T341C, T341G, S343E, M345T, K349E, L353A, L354I, N356E and I361T in wild-type PH20 having the amino acid sequence of SEQ ID NO: 1, and additionally comprise the substitution of amino acids located in the alpha-helix 8 region and / or a linker region between alpha-helix 7 and alpha-helix 8 in the amino acid sequence of wild-type PH20, and in which one or more amino acids located at the N-terminal and C-terminal regions are deleted.

The present invention belongs to the technical field of protein engineering. Provided are a recombinant type XVII collagen having a triple helix structure and the use thereof. The amino acid sequence of the recombinant type XVII collagen comprises n core units, wherein n is the integer 1 or an integer greater than 1, and the amino acid sequence of the core units is as shown in SEQ ID NO: 1. Further provided are a method for constructing a plurality of expression systems and a method for preparing the recombinant type XVII collagen. Further provided is the actual industrial application on the basis of the characteristics of the protein. The provided recombinant type XVII collagen exhibits high purity, good thermal stability and high biological activity, and has a molecular weight much smaller than that of natural collagen, thereby reducing the difficulty for the collagen to cross the skin barrier and exert biological functions. Experiments show that the recombinant type XVII collagen has a variety of biological activities such as promoting cell migration.

The invention discloses a recombinant human IV-type collagen as well as a preparation method and application thereof, and belongs to the field of bioengineering and protein engineering. According to the invention, three recombinant human IV type collagen new molecules are designed and screened on the basis of a part of sequences in a human IV type collagen alpha1 chain, soluble expression of a target protein is realized by using an escherichia coli system, and the recombinant collagen with the purity of more than 98% can be obtained through nickel column purification and acid regulation treatment. The recombinant collagen provided by the invention has good cell migration promotion activity and cell adhesion activity, and can be widely applied to the fields of tissue engineering, medical equipment, cosmetics, health care products and the like.

The invention discloses a polyphosphate kinase mutant, a biological material, a catalyst and application, and belongs to the field of protein engineering, and compared with a wild enzyme, the mutant has one or more amino acid residue mutations in the 307th site, the 311th site, the 320th site, the 408th site, the 419th site and the 431th site. The mutant disclosed by the invention is obtained by combining a semi-rational design strategy with active site region prediction and mutation library design screening, and the enzyme activity and the relative yield are remarkably improved: the efficiency of catalytic synthesis of GTP by using the preferable mutant Y431P / K311F / W408A with GMP as a substrate is 2.6 times that of a wild type enzyme, and the relative yield is improved by 150%; the efficiency of the optimized mutant Y431P / K311F / R419L for catalytically synthesizing GTP by taking GDP as a substrate is 1.9 times that of a wild enzyme, and the relative yield is increased by 82%. The key mutant obtained by screening can realize efficient synthesis from cheap NDP or NMP to high-value NTP, and has an excellent industrial application prospect.

The present disclosure provides a recombinant type XVII collagen with a triple helical structure and use thereof and belongs to the field of protein engineering technology. The recombinant type XVII collagen has an amino acid sequence formed by tandem repeats of n core units, wherein n is an integer of 1 or greater than 1, and the core unit has the amino acid sequence as set forth in SEQ ID NO: 1. The present disclosure also provides methods for constructing multiple expression systems and methods for preparing the recombinant type XVII collagen.

The invention provides recombinant IV type collagen and application thereof, and relates to the technical field of protein engineering. In the invention, an amino acid residue repetitive unit with good biological activity and stability in the human-derived IV-type collagen is found, and the amino acid residue repetitive unit is used as a core for repeating and constructing the recombinant IV-type collagen, so that the novel human-derived recombinant IV-type collagen with biological activity is obtained. The human-derived recombinant IV-type collagen provided by the invention is a small-molecular-weight protein, is easy to absorb by a human body, is good in safety, can remarkably promote secretion of collagen, also has the effects of promoting cell adhesion and cell migration, and has a good application prospect in the aspects of basement membrane repair and remodeling. A new functional component is provided for products for repairing and tightening the skin, resisting aging, resisting wrinkles, preserving moisture and the like.

The invention relates to the technical field of genetic engineering and protein engineering modification, in particular to an alkaline xylanase mutant with improved specific activity. Compared with a wild type, the specific activity of the xylanase mutant is improved by 32.83% and reaches 1574 U / mg, the production cost is reduced, and wide application of the xylanase mutant in the industrial field is promoted.

The invention belongs to the technical field of protein engineering modification, and particularly relates to a method for improving thermal stability of fumonisins degrading enzyme by forming disulfide bonds. The thermal stability of the fumonisins degrading enzyme FumDPS mutants T194V, T194V-P40C / Y173C, T194V-N43C / D83C and T194V-F71C / S117C related to the invention is obviously improved compared with that of the wild type fumonisins degrading enzyme, and the thermal stability of the fumonisins degrading enzyme FumDPS mutants is obviously improved. The fumonisins enzyme is mainly applied to the industries of livestock feed processing, food production and the like so as to reduce the harm of fumonisins to the health of animals and human beings. The obtained fumonisins degrading enzyme mutant with improved thermal stability is convenient to transport and store, so that the investment of industrial cost can be reduced.

The invention belongs to the technical field of protein engineering modification, and particularly relates to a fumonisins degrading enzyme mutant with improved specific activity and thermal stability and application. According to the mutants of the fumonisins degrading enzyme FumDSB, which are provided by the invention, the relative activity and the thermal stability of the mutants A373R, A373R / S248P, A373R / Q259P, A373R / T282D, A373R / G321A, A373R / D330P and A373R / A378K are obviously improved compared with those of a wild type fumonisins degrading enzyme. The enzyme is mainly applied to the industries of agricultural products, animal feed, food and the like so as to reduce the harm of fumonisins to the health of animals and human beings. The obtained fumonisins mutant with improved activity and thermal stability is beneficial to reducing the cost of the enzyme in industrial application.

The invention relates to a transaminase mutant, a coding gene, an engineering bacterium and an application of the transaminase mutant in synthesis of N-Boc-3-aminopiperidine. A mutant library of transaminase is constructed through protein engineering modification, a series of better transaminase mutants are obtained through screening, and compared with wild transaminase, the enzymatic activity of the mutant is obviously improved. On the basis, the optimal mutant Y113F / R126L is further screened, the enzymatic activity of the optimal mutant Y113F / R126L is 3.9 times that of wild transaminase, and the reaction conversion rate can reach 70.14%.

The present invention relates to the technical field of protein engineering and provides a recombinant humanized type III collagen having a triple helix structure, a preparation method therefor, and a use thereof. The amino acid sequence of the recombinant humanized type III collagen comprises n core units, wherein n is 1 or an integer greater than 1, and the amino acid sequence of the core unit is as shown in SEQ ID NO: 1. The present invention further provides a method for constructing an expression system and a method for preparing a recombinant humanized type III collagen. The present invention further provides an actual industrial use on the basis of the characteristics of the protein. The recombinant humanized type III collagen provided by the present invention has high purity, good stability, and high biological activity. Experiments have shown that the recombinant humanized type III collagen has various biological activities such as promoting cell proliferation and migration.

The invention relates to the technical field of biological detection, and particularly discloses a one-tube method detection system based on Cas protein modification and application of the one-tube method detection system. An epitope is inserted into the Cas protein, so that the cis-cleavage activity of the Cas protein is weakened. Starting from the Cas protein, the Cas is modified through a protein engineering strategy, the problem of competition between RPA amplification and Cas protein cleavage is successfully solved, and the one-tube method detection system based on Cas protein modification has the characteristics of quick response, high sensitivity, high reliability and simplicity and convenience in operation; and the kit has important practical significance on detection, prevention and treatment of early infection.

The invention relates to the technical field of molecular biology and protein engineering, in particular to a lactic acid bacteria antibacterial peptide LABA4 multi-copy expression method and application. The invention aims to provide a prokaryotic expression method of an antibacterial peptide LAB4 tandem gene based on a self-assembled peptide and application, so that the problems of toxicity to a host, low expression quantity and non-ideal product activity in a large intestine expression system are solved, the antibacterial peptide is efficiently expressed in escherichia coli, and the antibacterial activity is effectively improved. Particularly, the characteristics of specific cutting and no amino acid residue of enterokinase are utilized, modified recombinant enterokinase is added between LAB4 monomers to serve as an interval restriction enzyme cutting site, a gene shuffling technology is utilized to design and construct three-six copy tandem recombinant plasmids of LAB4, the self-cleavage characteristic of intein is utilized, and the recombinant enterokinase recombinant plasmids of LAB4 can be used for preparing the recombinant enterokinase recombinant plasmids of LAB4, so that the recombinant enterokinase recombinant plasmids of LAB4 can be used for preparing the recombinant enterokinase recombinant plasmids of LAB4. An optimized cspA cold shock promoter in a pCold I vector is adopted, and high-efficiency expression of tandem LAB4 in an escherichia coli expression system is realized through 15 DEG C low-temperature induction precise regulation and control.

The invention belongs to the technical field of protein engineering modification, and particularly relates to a method for improving thermal stability of fumonisins degrading enzyme by forming disulfide bonds. The thermal stability of the fumonisins degrading enzyme FumD mutant provided by the invention is obviously improved compared with that of wild type fumonisins degrading enzyme. The fumonisins enzyme is mainly applied to the industries of livestock feed processing, food production and the like so as to reduce the harm of fumonisins to the health of animals and human beings. The obtained fumonisins degrading enzyme mutant with improved thermal stability is beneficial to keeping the activity of the enzyme at a higher temperature, adapts to a higher-temperature production environment, reduces the use amount and replacement frequency of the enzyme, and is convenient to transport and store due to the improvement of the stability, so that the investment of industrial cost can be reduced.

The invention relates to the technical field of protein engineering or genetic engineering, and discloses a method for improving the secretory expression efficiency of sweet protein in pichia pastoris. The invention discloses pichia pastoris for secretory expression of sweet protein. The pichia pastoris simultaneously expresses a sweet protein gene, a secretory signal peptide gene and a gene expression regulatory element. The pichia pastoris is subjected to two-stage fermentation culture, the sweet protein can be successfully prepared, and the yield is 4g / L or above. The technical scheme provided by the invention has an extremely high effect of improving the secretory expression efficiency of the sweet protein.

The invention belongs to the technical field of gene engineering and protein engineering, and particularly relates to thermal-stable D-psicose 3-epimerase as well as a preparation method and application thereof. According to the invention, a series of D-psicose 3-epimerase DAE mutants are constructed, and six mutants which not only can retain good catalytic activity, but also have high thermal stability are obtained through screening. The catalytic temperature of the three mutants A19D / A223P / V241I is increased by 25 DEG C compared with that of a wild type, while the three mutants A19D / A223P / V241I still show the optimal thermal stability, the catalytic activity of the three mutants is improved by 17.0%, and the three mutants show good industrial suitability. The D-psicose 3-epimerase DAE mutant with improved thermal stability provided by the invention is beneficial to improving the production efficiency of the DAE in industrial application of D-psicose, and provides powerful industrial enzyme guarantee for large-scale and low-cost preparation of D-psicose.

The invention relates to the technical field of functional gene and protein engineering, and discloses an amino acid sequence, a gene sequence, an expression vector and application of medicago ruthenica MrAGL8 protein, the amino acid sequence of the medicago ruthenica MrAGL8 protein is as shown in SEQ ID NO.1, the gene sequence for coding the medicago ruthenica MrAGL8 protein is as shown in SEQ ID NO.2, and the gene sequence for coding the medicago ruthenica MrAGL8 protein is as shown in SEQ ID NO.1. The invention further discloses application of the medicago ruthenica MrAGL8 protein to construction of an early-maturing plant strain or a low-pod-cracking-rate plant strain. Experiments show that the MrAGL8 gene plays an important role in promoting the early maturing of plants and reducing the pod cracking rate, and by utilizing the phenomenon that the found MrAGL8 gene participates in the response reaction of plant growth and development and pod cracking, the MrAGL8 gene is used for constructing an early maturing plant strain or a low pod cracking rate plant strain and carrying out heterologous overexpression; therefore, early maturing of transgenic plants is effectively promoted, and the pod cracking rate is remarkably reduced.

The invention provides a recombinant I-type collagen with a thermostable triple helix structure and application thereof, and belongs to the technical field of protein engineering, the amino acid sequence of the recombinant I-type collagen is shown as SEQ ID NO: 1; the invention also provides a construction method of the expression system and a preparation method of the recombinant I-type collagen. The invention also provides practical industrial application according to the characteristics of the protein.

The invention belongs to the technical direction of protein engineering in the technical field of biology, and particularly relates to a triple-helix folding and stabilizing method for recombinant collagen, which is a technology for efficiently assisting correct folding of human recombinant collagen expressed by escherichia coli and forming a stable triple-helix structure. The technology mainly solves the common key technical problems of low folding efficiency, unstable triple helix structure and the like of the recombinant collagen in an escherichia coli expression system, and obviously improves the yield of the functional recombinant collagen. The method has important application value in the fields of biomedical materials, tissue engineering, beauty and skin care and the like, and an efficient and economical technical path is provided for industrial production of recombinant collagen.

The invention belongs to the technical field of biological medicine, and particularly relates to application of antifreeze protein in weight losing and blood sugar reducing. The NPAFP transgenic mouse model is successfully constructed by utilizing a genetic engineering technology, and the potential application value of the NPAFP protein in weight loss and blood sugar reduction is verified. Furthermore, based on the model, it is found that the NPAFP protein has remarkable effects in the aspects of reducing fat accumulation and improving the blood glucose level by adjusting brown fat metabolism and the liver lipid droplet content. Based on compound development or protein engineering modification of the NPAFP protein, novel drugs and strategies can be provided for treatment of obesity and diabetes mellitus. Meanwhile, the molecular mechanism of the NPAFP protein is further explored by combining a multi-omics technology, and clinical transformation and application of the NPAFP protein are promoted.

The invention discloses an ILTV gD protein antigen epitope expression cassette, a recombinant virus and application, and relates to the field of gene and protein engineering. The ILTV gD protein antigen epitope expression cassette provided by the invention comprises T and B cell epitopes of gD protein derived from an infectious laryngotracheitis virus WG strain. The recombinant virus rH120-gD-T / B is obtained by replacing a 5ab gene of an infectious bronchitis virus H120 strain with a gene for coding an ILTV gD protein antigen epitope expression cassette. The recombinant virus has good genetic stability, can be used for developing a safe and effective IB-ILT bivalent live vector vaccine, and solves the problem of poor stability of the current recombinant IBV.

The invention provides a recombinant III-type collagen with a triple helix structure as well as a preparation method and application thereof, and relates to the field of protein engineering. According to the invention, a novel humanized III-type collagen functional fragment with biological activity is obtained through screening by selecting low-immunogenicity and high-biological activity blocks after complete sequence analysis of human III-type collagen. The functional fragments obtained by screening are repeatedly combined to obtain the novel recombinant humanized III-type collagen, and the recombinant humanized III-type collagen is a novel protein with strong biological activity and low immunogenicity, and provides a novel raw material for medical instruments and skin care products. The recombinant humanized III-type collagen sequence is efficiently expressed by adopting engineering bacteria, the expression level is high, the purification method is simple, and the recombinant humanized III-type collagen sequence is suitable for industrial production and wide popularization.

The invention discloses a method for improving the soluble expression of terminal deoxynucleotidyl transferase (TdT), and relates to the technical field of protein engineering and gene engineering, in particular to a method for improving the soluble expression of the TdT. TdT (TdT-B) with the BRCT structural domain removed serves as initial enzyme, hydrophilic amino acid replacement is conducted on hydrophobic amino acid on the surface of the TdT-B enzyme, and a TdT mutant is obtained. The mutant does not need any fusion tag and can be rapidly expressed under induction conditions of high temperatures such as 30 DEG C and 37 DEG C, the soluble protein expression level is remarkably improved, a large amount of soluble TdT is obtained in a short time, the soluble expression level of the TdT is remarkably improved, the fusion tag cutting step is not needed in subsequent downstream treatment, and the preparation method is simple and low in cost.

The invention relates to a chicken beta-defensin-6 mutant based on AI aided design, a recombinant expression system and application, and relates to the technical field of gene engineering and protein engineering. The chicken beta defensin-6 mutant has the following amino acids at the following five sites: lysine at the 33rd site, lysine at the 35th site, asparagine at the 49th site, arginine at the 61st site and proline at the 65th site. The chicken beta-defensin-6 mutant has high stability, activity and solubility, compared with wild chicken beta-defensin-6, the chicken beta-defensin-6 mutant has higher antibacterial activity and expression level, an efficient and safe antibacterial substitute is provided for livestock and poultry breeding, and the chicken beta-defensin-6 mutant can be widely applied to the fields of livestock and poultry breeding, animal health care and biological preservation.