555 results about "Protein engineering" patented technology

The invention provides a recombinant humanized III-type collagen with a triple helix structure and preparation and application thereof, and belongs to the technical field of protein engineering, the amino acid sequence of the recombinant humanized III-type collagen comprises n core units, n is an integer of 1 or greater than 1, and the amino acid sequence of each core unit is as shown in SEQ ID NO: 1; the invention also provides a construction method of the expression system and a preparation method of the recombinant humanized III-type collagen. The invention also provides practical industrial application according to the characteristics of the protein. The recombinant humanized III-type collagen provided by the invention is high in purity, good in stability and high in biological activity, and experiments show that the recombinant humanized III-type collagen has various biological activities of promoting cell proliferation and migration and the like.

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 genetic engineering, and particularly relates to recombinant IV-type humanized collagen as well as a preparation method and application thereof. A section of brand new recombinant collagen is designed and obtained through methods such as screening, replacement and splicing, the nucleotide sequence of the recombinant collagen is optimized through pichia pastoris codon preference, then a corresponding genetic engineering yeast strain is constructed and obtained, and the recombinant collagen is successfully prepared through fermentation. Experiments prove that the recombinant IV-type humanized collagen prepared by the invention is large in molecular weight and high in yield, and compared with commercially available recombinant collagen, the recombinant IV-type humanized collagen has better free radical scavenging performance and cell proliferation and migration promoting performance, and has good antioxidant and skin barrier repair functions, so that the recombinant IV-type humanized collagen has good practical application value.

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 relates to the technical field of gene engineering and protein engineering, in particular to a high-temperature-resistant lipase mutant. Compared with wild lipase RL, the lipase mutant containing V274T single-point mutation provided by the invention has the advantages that the heat resistance is obviously improved, the enzyme activity residual rate is up to 66.48% after the lipase mutant is treated at 80 DEG C for 3 minutes, and an unexpected technical effect is achieved. The lipase mutant is high in heat resistance, and wide application of the lipase mutant in the fields of feed production, grease processing and the like is facilitated.

The invention relates to the technical field of gene engineering and protein engineering, in particular to a lipase mutant. Compared with wild lipase RL, the lipase mutant containing P313L single-point mutation provided by the invention has the advantages that the heat resistance is obviously improved, the enzyme activity residual rate reaches up to 75.77% after the lipase mutant is treated at 80 DEG C for 3 minutes, and an unexpected technical effect is achieved. The lipase mutant is high in heat resistance, and wide application of the lipase mutant in the fields of grease processing and the like is facilitated.

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 belongs to the technical field of biology, and particularly relates to a latex duplex immunochromatography test strip for rapidly identifying a porcine transmissible gastroenteritis virus (TGEV) and a porcine epidemic diarrhea virus (PEDV) and a preparation method of the latex duplex immunochromatography test strip. Soluble TGEV N protein and PEDV N protein with immunogenicity and reactivity are respectively obtained by utilizing a prokaryotic expression system, the soluble TGEV N protein and the soluble PEDV N protein are used as immunogenicity to immunize mice, and specific monoclonal antibodies of the TGEV N protein and the PEDV N protein are respectively obtained by utilizing cell fusion and subcloning screening technologies. The antibody variable region gene sequence is obtained by using a nested PCR amplification technology, and can be subsequently obtained by using a gene engineering or protein engineering method. Then, the latex duplex immunochromatography test strip for detecting TGEV and PEDV, which is convenient, rapid and high in sensitivity, and the preparation method are researched and developed on the basis of specific monoclonal antibodies of TGEV N protein and PEDV N protein.

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 provides recombinant human III-type collagen as well as a preparation method and application thereof, and belongs to the technical field of protein engineering, the amino acid sequence of the recombinant human III-type collagen is shown as SEQ ID No.1, and the nucleotide sequence of a gene for coding the recombinant human III-type collagen is shown as SEQ ID No.2; the invention also provides a method for expressing the recombinant human III type collagen in mammalian cells. The recombinant human III-type collagen provided by the invention is high in purity, has triple helix characteristic circular dichroism, has the molecular weight of 21.8 kDa, is far smaller than that of natural full-length collagen, has the effects of promoting cell proliferation and cell migration, and reduces obstacles for the collagen to penetrate through a skin barrier to exert biological functions.

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 invention discloses a transformation method and application of a G protein coupled receptor, and belongs to the technical field of protein engineering. In order to improve the molecular weight of membrane protein, enable the enlarged part of the membrane protein and the original membrane protein to form a relatively rigid structure and further meet the structural analysis requirement of a cryoelectron microscope, the invention provides a method for transforming a G protein coupled receptor. The method comprises the following steps: co-expressing fusion protein GPCR (Glycine Polymerase Chain Reaction)-GFP10-11 and GFP1-9 fragments formed by GPCR and GFP10-11 fragments in a eukaryotic cell expression system, and adding GFP-clamp in the purification process; one amino acid at the specific site of GPCR is mutated into cysteine, glutamic acid at the 186th position of the amino acid sequence of GFP-clamp is mutated into cysteine, and a disulfide bond is formed between the amino acid and glutamic acid. The molecular weight of the modified G protein coupled receptor obtained by using the method can be increased to 85 kD or above, and the rigidity of the whole compound space structure is relatively strong, so that the modified G protein coupled receptor can be used for structural analysis of a cryoelectron microscope.

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 belongs to the fields of protein engineering and biotechnology, and particularly relates to an acetohydroxy acid synthase mutant and application thereof. The acetohydroxy acid synthase mutant capable of improving the yield of branched chain amino acid of the strain is obtained through deep research and mutant library screening, can be applied to production of L-leucine, L-isoleucine and L-valine, and has potential application prospects.

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 discloses a xylanase mutant with synchronously improved thermal stability and pH tolerance and application of the xylanase mutant, and belongs to the field of gene engineering and protein engineering. According to the invention, xylanase AbXyL10A from Agaricus bisporus var burnettii is taken as a female parent, and two amino acid sites of Thr234 and Arg268 are subjected to mutation, so that two types of xylanase mutants T234N and R268L are obtained. Compared with wild type xylanase, the thermal stability and pH tolerance of the two xylanase mutants are obviously improved. In the aspect of specific activity, when the beech xylan is used as a substrate, the specific activity of the two xylanase mutants is obviously improved compared with that of wild type xylanase. The invention provides a theoretical reference for the improvement of xylanase, and the obtained xylanase mutant with synchronously improved thermal stability and pH tolerance has a huge application prospect in the aspects of animal feed and biomass degradation sugar production.

The invention belongs to the fields of protein engineering and biotechnology, and particularly relates to an acetohydroxy acid synthase mutant and application thereof. The acetohydroxy acid synthase mutant capable of improving the yield of branched-chain amino acid of a strain is obtained through deep research and mutant library screening, can be applied to production of branched-chain amino acid including L-leucine, L-isoleucine and L-valine, and has potential application prospects.