197 results about "Foreign protein" patented technology

The invention relates to a protein for improving the expression yield of a foreign protein and application of the protein. Wherein the ERV29 protein and the related protein as well as the P180 protein and the related protein can be used as molecular chaperones for improving the expression yield of foreign proteins such as Brazilian sweet and the like; the amino acid sequence of the ERV29 protein is as shown in SEQ ID No. 4; the amino acid sequence of the P180 protein is as shown in SEQ ID No. 6.

The invention discloses a mammalian cell expression vector, an expression plasmid and an expression system. The expression vector sequentially comprises the following elements: (a) a promoter; (b) a Kozak sequence; (c) a polyadenine sequence, the polyadenine sequence sequentially comprises a bGH PolyA sequence and a 5 'UTR PolyA sequence, the nucleotide sequence of the bGH PolyA sequence is as shown in SEQ ID NO.5, and the nucleotide sequence of the 5' UTR PolyA sequence is as shown in SEQ ID NO.6; (d) copying the start site; and (e) screening marker genes. According to the present invention, the expression vector is optimized by the expression element, such that the exogenous gene can be conveniently, efficiently and flexibly inserted and edited by the expression vector so as to achieve the stable extracellular or intracellular expression of the exogenous protein, and the expression efficiency of the exogenous protein can be improved by carrying out the expression plasmid construction based on the expression vector; and more efficient expression and purification of the foreign protein are realized.

This invention provides an in vitro cell-free protein synthesis system, its reagent kit, and its applications, belonging to the field of protein synthesis technology. This invention improves an in vitro cell-free protein synthesis system based on Kluyveromyces lactis by adding exogenous L-arabinose, significantly enhancing the system's protein synthesis capacity. Furthermore, it provides a more efficient and higher-throughput in vitro protein synthesis reagent kit and a method for synthesizing exogenous proteins. The improvements provided by this invention can be achieved without molecular modification, are simple and convenient to operate, and save costs.

The invention discloses a preparation method of polydeoxyribonucleotide, and relates to the technical field of synthetic biology, and the preparation method comprises the following steps: S1, randomly selecting n ssDNAs from a salmon genome sequence; s2, carrying out cyclization on the ssDNA, so as to obtain cssDNA; s3, carrying out amplification on the cssDNA to obtain a repeated long single-stranded DNA (Deoxyribose Nucleic Acid); and S4, breaking the repeated long single-stranded DNA to obtain the PDRN. According to the method, a large amount of repeated long single-stranded DNA can be synthesized only by introducing a small amount of foreign proteins (T4DNA ligase and Phi29 DNA polymerase), the repeated long single-stranded DNA is broken by a physical breaking method, and a large amount of PDRN products with ideal molecular weight can be obtained in a short time.

The invention provides a method for constitutive expression of foreign protein by escherichia coli Nissle 1917, and belongs to the technical field of genetically engineered bacteria. The invention provides a method for constitutive expression of foreign protein by Escherichia coli Nissle 1917 (EcN), which is characterized in that EcN is used as a chassis strain, an engineering strain for constitutive expression of the foreign protein is constructed by transforming a covert plasmid, and high-efficiency expression of the foreign protein can be realized without induction of an inducer and antibiotic pressure. By utilizing the method disclosed by the invention, the EcN engineering bacterium for constitutive expression of the foreign protein RtSOD is successfully constructed, constitutive efficient expression of the high-stability RtSOD protein in the EcN engineering bacterium can be realized without using antibiotic pressure and inducer induction, and the EcN engineering bacterium can be used as a potential viable bacterium medicine for preventing and treating oxidative stress related diseases and has a wide application prospect. And the method has important significance on the practical application of the EcN engineering strain.

The present invention relates to a recombinant human type IV collagen and a preparation method therefor, which belong to the technical field of bioengineering. A recombinant human type IV collagen is designed on the basis of a partial sequence in an α2 chain of human type-IV collagen, and DNA encoding of the protein is ligated into an expression vector to construct a recombinant expression vector; then the recombinant expression vector is transformed into competent Escherichia coli cells, and a recombinant expression plasmid is extracted; after the plasmid is linearized, the linearized plasmid is transformed into an engineered strain HCPB-PPKEX2 to obtain a recombinant engineered strain; and the engineered strain is cultured, the expression of a target protein is induced, and the target protein is purified and identified. It is further demonstrated experimentally that the collagen can be completely cleaved by Kex2, Ste13 and CPB enzymes and efficiently secreted and expressed extracellularly, and the obtained sequence is completely consistent with a theoretical sequence. It is also verified experimentally that the recombinant collagen has a cell adhesion activity and a cell migration-promoting activity. The method avoids the risk of residual exogenous proteins, shortens the time and reduces the cost of the subsequent purification process, and thus has a relatively high safety and application value.

The invention provides application of a porcine parainfluenza virus type 5 as an expression vector, and belongs to the technical field of biological vaccines. According to the invention, a PIV5 strain separated from diarrhea pigs in Jiangsu Province in China is utilized to construct PIV5 virus infectious clone. The eGFP gene is inserted into a PIV5 infectious cloned virus genome, the recombinant PIV5 virus capable of expressing the green fluorescent protein is successfully rescued, and when the eGFP gene is inserted into a P / M gene spacer region, the expression quantity is the highest, which indicates that an exogenous gene expression cassette can influence the expression level of an exogenous gene, and the P / M gene spacer region is the optimal site for inserting the exogenous gene, so that the recombinant PIV5 virus can be successfully rescued. And a solid foundation is laid for developing a vector vaccine by utilizing the swine PIV5. The porcine parainfluenza virus type 5 can be used as an expression vector to express foreign proteins, can also be used for preparing oral vaccines, and can relieve the stress reaction of pigs in the immune process.

The invention relates to a protein combination for influencing the growth rate of yeast and the expression quantity of foreign proteins. After genes in a peptidase A1 family, a peptidase M1 family, a peptidase M18 family, a peptidase M28 family, a peptidase S54 family, a peptidase S10 family, a peptidase S16 family, a peptidase S14 family and a peptidase S8 family and protein defect related genes are knocked out as transcription activating factors, the growth rate can be increased, and the expression quantity of foreign proteins can be increased.

The invention belongs to the technical field of biological medicine, and discloses lactococcus lactis HX21473 and application thereof, the lactococcus lactis HX21473 is preserved in China General Microbiological Culture Collection Center (CGMCC) on January 20, 2025, and the preservation number is CGMCC NO.33476. The invention further discloses a preparation method of the lactococcus lactis HX21473. The invention provides a strain of lactococcus lactis HX21473 capable of efficiently expressing a foreign protein. The lactococcus lactis HX21473 has strong acid resistance, can be used as an oral vaccine live carrier, and promotes research, development and application of oral vaccines.

The application provides an in-vitro cell-free protein synthesis system and kit containing exogenous magnesium ions and application thereof, including a D2P system (DNA-to-Protein system) and an mR2P system (mRNA-to-Protein system), and belongs to the technical field of protein synthesis. The in-vitro cell-free protein synthesis system containing exogenous magnesium ions adopts magnesium aspartate as a novel magnesium ion source, and especially in a eukaryotic cell-free system, compared with a traditional magnesium ion source, can significantly improve the protein synthesis efficiency and protein expression amount. A more efficient and higher-throughput in-vitro protein synthesis kit and a synthesis method of exogenous proteins are also provided, and the kit has the advantages of simplicity, convenience and low cost.

The invention discloses a novel plasmid vector capable of increasing CHO foreign protein expression quantity and construction and application thereof, and belongs to the technical field of gene engineering. The plasmid vector pCHO6GS belongs to a brand-new plasmid system, and the expression quantity of a common monoclonal antibody and recombinant protein (such as H5HA trimer) difficult to express in CHO can be increased by at least more than one time, so that the expression quantity of foreign protein is increased beyond expectation through the novel plasmid vector; and the method also plays an extremely important role in reducing cost and improving efficiency of various protein products taking CHO as a cell factory.

The invention provides a preparation method, application and the like of large intestine expression recombinant A-type botulinum toxin (BONT / A). The recombinant BONT / A nucleic acid expression cassette comprises a tag, a restriction enzyme cutting site and a BONT / A nucleic acid sequence, and an exogenous protease recognition site is not introduced between a BONT / A light chain and a BONT / A heavy chain. The invention also provides a recombinant vector containing the nucleic acid expression cassette, a recombinant bacterium, a coded and expressed protein and the like, the prepared recombinant BONT / A does not introduce exogenous amino acid or only introduces two amino acids at one position, and the consistency of the recombinant BONT / A with the natural A-type botulinum toxin is ensured to the greatest extent. Through novel molecular design and preparation process, the recombinant reBONT / A with higher toxicity and low immunogenicity is efficiently obtained, and wide industrial application is facilitated.

The invention discloses a method for quickly rescuing bovine coronavirus epidemic strains and application of the method. The bovine coronavirus SHZ isolate is subjected to efficient segmented cloning, the obtained segment and a Linker sequence are subjected to a cyclic polymerase extension reaction, and the obtained reaction product can be directly transfected to 293T cells for virus packaging without purification. Different from a traditional method, the method does not need to amplify full-length virus cDNA clone by means of bacteria and yeast, but directly obtains a sufficient amount of preliminary products through PCR, and avoids the problems of instability and low efficiency when partial sequences of a virus genome proliferate in a bacteria or yeast host. By adopting the reverse genetic system, the recombinant bovine coronavirus expressing the foreign protein is successfully rescued, a brand new technical platform is provided for dynamic visualization research of in-vivo and in-vitro replication of the virus, and an efficient and flexible tool is also provided for virology research, development of virus vector vaccines and screening of antiviral drugs.

The present invention belongs to the biological field, and specifically relates to a polynucleotide based on a CMV promoter and its application. The present invention constructs a plasmid containing a strong promoter for cell expression, introduces a random mutation CMV promoter through random mutation PCR technology, and screens to obtain a stronger CMV promoter sequence. The CMV promoter sequence obtained in the present invention can significantly increase the expression amount of an exogenous target protein, and provides a basis for increasing the expression amount of an exogenous protein in transient and stable transfection.

The invention discloses a sugarcane streak mosaic virus infectious cloning vector as well as a construction method and application thereof, and belongs to the technical field of biology. The recombinant plasmid provided by the invention contains a whole genome of the SCSMV, and the nucleotide sequence of the whole genome is the 771 to 10583 nucleotides of SEQ ID No. 1. The recombinant plasmid disclosed by the invention is obtained by taking a pCB301 vector as a skeleton and then inserting the skeleton into a whole genome of SCSMV, and the recombinant agrobacterium tumefaciens (pCB301-SCSMV infectious clone) prepared by the recombinant plasmid can successfully infect nicotiana benthamiana and has efficient infection ability; the infectious clone of the recombinant expression plasmid prepared from the recombinant plasmid can successfully infect nicotiana benthamiana, has efficient infection ability and can express foreign proteins.

The invention discloses a signal peptide SEQ ID NO: 1-3 suitable for yeast, the coding gene of the signal peptide is expressed in the yeast after being fused with a foreign protein gene, the expression level of the foreign protein can be improved, and the signal peptide has popularization and application prospects.

The invention belongs to the technical field of genes, and discloses a method for efficiently expressing foreign protein based on an NC048599.1 site in a CHO cell genome. A site for stably expressing a protein in a CHO cell genome is located in a range of 69195000 to 69199000 of a CHO cell gene NC048599.1 with a sequence as shown in SEQ ID NO: 1 (Sequence Identifier Number 1), and the sequence of the CHO cell gene NC048599.1 is shown in SEQ ID NO: 1. Different protein genes are introduced at fixed positions in a CHO cell genome, and stable expression is carried out.

The invention provides a preparation method of a recombinant cell, the recombinant cell and application of the recombinant cell, and relates to the technical field of biology. A target protein expressed by the recombinant cell contains one, two, three or four polypeptide chains; the preparation method comprises the following steps: integrating exogenous polynucleotides for coding a target protein into a genetic material of a starting cell in a site-specific manner, wherein each exogenous polynucleotide for site-specific integration contains coding genes of all polypeptide chains of the target protein; each exogenous polynucleotide contains at least four expression cassettes, and each polypeptide chain is encoded by at least one expression cassette. The preparation method is simple to operate, coding genes of all polypeptide chains can be integrated into genetic materials of starting cells at a time, and the expression quantity of foreign proteins of the recombinant cells obtained through the preparation method is high.

The invention relates to the technical field of genetic engineering, in particular to recombinant human collagen as well as a preparation method and application thereof. The recombinant human collagen provided by the invention is a polypeptide containing an amino acid sequence such as SEQ ID No.1. The recombinant human collagen disclosed by the invention is expressed at a high level outside cells, the culture is easy to amplify, the target protein can be produced at high yield by utilizing a high-density fermentation mode, secretory expression is beneficial to separation and purification of an expression product and reduction of production cost, and the recombinant human collagen has a certain post-translational modification function, such as glycosylation and the like, on the expressed foreign protein.

To provide a new method for efficiently purifying an exogenous protein expressed in a plant.SOLUTION: A method for purifying a foreign protein expressed in a plant, comprising the step of adding an acid to an extract of a tissue of a plant in which a foreign protein is expressed to degrade contaminating proteins derived from the plant.SELECTED DRAWING: None

The invention discloses a PVX expression vector pWX for efficiently expressing foreign protein and application of the PVX expression vector pWX. In the construction process of optimizing potato X virus infectious clone, after a single base mutation NruI-gene sequence (CCGCGA) is inserted into an upstream regulation region of a PVX coat protein subgene promoter, a novel PVX expression vector capable of promoting foreign protein expression is obtained, and the novel PVX expression vector is named as pWX. Experiments prove that compared with a control vector, the accumulation amount of GFP (Green Fluorescent Protein) generated by the pWX vector through transient expression of agrobacterium in tobacco is obviously increased. The invention further applies a pWX vector to successfully express an important target protein HPV16L1 researched and developed by an HPV vaccine, and the expression quantity of the important target protein HPV16L1 in tobacco is 5.25 micrograms per gram of fresh heavy leaves. The invention provides a novel vector based on a PVX genome for high-efficiency expression of a plant source target protein, and the vector has a good application prospect in preparation of plant source vaccines.

The invention relates to a Sebastes schlegeli endogenous retrovirus envelope protein Penv, a lentiviral vector and application thereof, and belongs to the field of genetic breeding of molecular biology, and the amino acid sequence of the envelope protein Penv is as shown in SEQ ID NO.1. The invention further provides an in-vitro assembly system, a transformant and a kit containing membrane fusion protein particles and lentiviral particles of the envelope protein Penv and application of the envelope protein Penv. VSVG protein is replaced with Penv protein from sclerobone fish, so that the transduction efficiency of the lentiviral particles to sclerobone fish cells is effectively improved, and the transduction efficiency of the lentiviral particles to the sclerobone fish cells is improved. And efficient gene delivery is realized. Meanwhile, as the endogenous Env protein, the Env protein overcomes the immunological rejection of a host to the exogenous Env protein, and also has the potential of in-vivo application.

The present invention discloses a VHH chain of an anti-APP nanobody and its application. The anti-APP nanobody of the present invention has the following beneficial effects: (1) small molecule and drug delivery. (2) easy to manufacture and express. (3) high affinity and strong specificity. (4) stable performance and good plasticity. (5) low immunogenicity and good metabolic characteristics. The APP nanobody of the present invention retains the ability of the VVH chain antibody and avoids the introduction of non-human exogenous proteins as much as possible, taking into account the function of effectively binding to anti-APP and the lowest possible heterology. In addition, the reduction of heterology can not only reduce hypersensitivity reactions but also prolong its half-life in the body and improve metabolic characteristics.

The invention provides an in-vitro cell-free synthesis method and kit of foreign protein, and belongs to the technical field of protein synthesis. According to the in-vitro cell-free synthesis method of the foreign protein, a water-phase in-vitro cell-free protein synthesis system and a nucleic acid template for coding the foreign protein are provided, a hydrophobic interface in surface contact with the water-phase in-vitro cell-free protein synthesis system is provided, incubation reaction is carried out, the foreign protein is synthesized, and the in-vitro cell-free synthesis method of the foreign protein is obtained. The protein synthesis efficiency and the protein expression quantity of the cell-free system are improved. The invention further provides an in-vitro protein synthesis kit which is more efficient and higher in throughput. The invention provides a simple and convenient hydrophobic interface optimization method which is simple and convenient to operate and saves cost.

The invention relates to a combined additive, a CHO cell culture medium, a preparation method and a culture method. The combined additive comprises cyclohexyl alanine and 3-(2-naphthyl)-L-alanine. The CHO cell culture medium comprises amino acids, vitamins, trace elements, inorganic salts, lipids, carbohydrates and a combined additive, the preparation method is used for preparing the CHO cell culture medium. The culture method uses a CHO cell culture medium to culture CHO cells. The combined additive is obtained through structural domain virtual docking and hydrophobicity regulation and control screening, G1 / S conversion can be mildly delayed, cell apoptosis can be inhibited, and an expression window can be prolonged. The culture medium contains amino acids, vitamins, trace elements and the like, and preferably selects a functional additive to replace serum and foreign protein functions. According to the application, high proliferation of CHO cells and efficient target protein expression can be realized under the conditions of no serum and no foreign protein, meanwhile, the accumulation of lactic acid and ammonia is reduced, the cell caking phenomenon is reduced, and the application has remarkable technical advantages.

The invention belongs to the technical field of biological genetic transformation, and relates to a method for preparing recombinant foreign protein based on transient expression of fruits of cucurbitaceae crops. The efficient expression of the foreign protein is realized through the processes of constructing an instantaneous transformation vector, infecting fruits with agrobacterium and purifying the protein. The method overcomes the defects of high cost and low purity of a traditional tobacco transient expression system, has the advantages of easily available raw materials, large biomass, edibility, high safety and the like, and provides a new way for low-cost large-scale production of recombinant proteins.

The invention belongs to the technical field of chemiluminescence detection, and particularly relates to a kit for detecting a bovine leukemia virus IgG antibody as well as a detection method and application of the kit. A sample treatment solution in the kit is prepared from Protein A, disodium hydrogen phosphate dodecahydrate, monopotassium phosphate, potassium chloride, sodium chloride, casein, mercaptoethanol, Tween-20 and Proclin; and the mark of the magnetic bead is sealed by combining PEG4000 and ethanolamine. Compared with traditional single protein sealing, the sealing mode provided by the invention has the advantages that interference of foreign protein is removed, non-specific binding in a sample is reduced, the background is reduced, and the stability, sensitivity and specificity of detection are improved; compared with a traditional large-proportion diluted sample, the sample treatment liquid has the advantages that excessive IgG in the sample is removed, dilution treatment of an equipment dilution module is not needed in the detection process, manual pre-dilution treatment is also not needed, and the detection efficiency is improved.

The invention relates to the technical field of biology, in particular to a protease gene modified vector and application thereof. The method comprises the following steps: designing a protease SBT6.1 instantaneous silencing fragment, constructing a TRV2: SBT6.1 vector by using a homologous recombination technology, and injecting the TRV2: SBT6.1 vector to a two-week-old Bensi tobacco leaf by using agrobacterium to obtain a plant with high expression quantity of foreign protein. After the protease SBT 6.1 is instantaneously silenced, the expression quantity of the exogenous target protein is obviously increased, the aim of improving a nicotiana benthamiana bioreactor is fulfilled, and the method has important application value in production.

The invention belongs to the technical field of biological medicine, and discloses lactococcus lactis HX9302 for expressing foreign protein and application, the lactococcus lactis HX9302 is preserved in China General Microbiological Culture Collection Center on January 20, 2025, and the preservation number is CGMCC NO.33477. The lactococcus lactis HX9302 is preserved in China General Microbiological Culture Collection Center on January 20, 2025; the lactococcus lactis has good acid resistance and digestive enzyme tolerance, can be used as an oral delivery live carrier of helicobacter pylori vaccines, and promotes research, development and application of oral vaccines.