20 results about "Coat Proteins" patented technology

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 discloses a composite material, a preparation method of the composite material, a thin film and a photoelectric device, the composite material comprises tobacco mosaic virus and metal nanoparticles, and the metal nanoparticles are combined with coat protein of the tobacco mosaic virus. Part of peptide chains in the coat protein of the tobacco mosaic virus and different types of metal nanoparticles have special binding energy, so that the metal nanoparticles can be orderly assembled on the coat protein of the tobacco mosaic virus, the problem that the metal nanoparticles are easy to agglomerate is effectively improved, and the composite material can be applied to photoelectric devices and has good application prospects. The photoelectric performance and the service life of the photoelectric device can be improved.

The invention belongs to the field of enzyme engineering and agricultural waste conversion, and particularly relates to an acid-resistant and heat-resistant nitrilase mutant and application thereof in fermentation of rapeseed meal. Aiming at the conditions that the existing nitrilase is insufficient in acid resistance and heat resistance and relatively low in activity, the nitrilase RsNit anchored on the surface capsid protein cotG of bacillus subtilis DB403 is used as a starting target for modification; according to the nitrilase mutant disclosed by the invention, a catalytic hot spot existing in an active center is found by carrying out semi-rational design on amino acid at the active center, and combined mutation is carried out on the catalytic hot spot, so that it is found for the first time that RsNit has a catalytic hot spot on 4-pentenenitrile at the active center, and a nitrilase mutant of which the activity, the thermal stability and the acid tolerance are all remarkably improved is successfully screened out; the method is applied to fermentation of the rapeseed meal, so that full utilization of the rapeseed meal in livestock and poultry feed is promoted, and the method has a wide market application prospect.

The application discloses a kind of MS2 virus-like particles based on capsid protein site-directed mutation and its preparation method and application, belong to molecular biological technique field.The amino acid of the beta sheet interface of capsid protein sequence, the amino acid of the interface when two capsid proteins molecules assemble, the carboxyl end site of capsid protein is subjected to site-directed mutation, obtain the mutant that can significantly improve the assembly efficiency and stability of capsid protein dimer.Utilize the mutant to construct MS2 virus-like particles, further by the design of mature enzyme and capsid protein expression element, control mature enzyme weak expression, capsid protein strong expression, to improve assembly efficiency.The application improves the assembly efficiency of MS2 virus by the above strategy, improves the proportion of wrapped RNA, enhances the stability of virus-like particle, greatly prolongs the stable storage time of RNA, improves the purity of wrapped RNA.

The invention discloses a protein nano material as well as a preparation method and application thereof. The protein nano material comprises a disc-shaped self-assembly body formed by tobacco mosaic virus capsid protein and a peptide fragment containing RGD motif and presented on the surface of the disc-shaped self-assembly body, the peptide fragment containing the RGD motif is presented on the surface of the discoid self-assembly body in a multivalent form, and the peptide fragment containing the RGD motif contains at least two cysteine residues. According to the protein nanomaterial, the tobacco mosaic virus capsid protein disc-shaped self-assembly body is used as a support, stable multivalent presentation of the RGD motif peptide fragment is achieved on the surface of the support, and therefore stable and consistent adhesion sites can be provided on the culture surface; meanwhile, the material composition is clear, the preparation process is controllable, the batch difference is reduced, and the repeatability and reliability of cell culture and related application are improved.

The present disclosure relates to a single stranded RNA vector suitable for introducing a therapeutic agent, such as a peptide, a protein or a small RNA, into a host plant. The vector does not encode for any movement protein or coat protein, but is capable of capable of systemic and phloem-limited movement and replication within the host plant.

The invention relates to a recombinant adenovirus nucleic acid wherein the gene encoding protein V and / or the gene encoding protein VII is placed under control of a heterologous promoter, to a recombinant adenovirus nucleic acid wherein the adenoviral nucleotide sequence is mutated in such a way that it is no longer capable of producing one or more of the coat proteins, to cellular vesicles filled with such adenoviral material, cells provided with such adenoviral material and to methods and use thereof.

This invention discloses an RNAi recombinant vector resistant to both whitefly and tomato yellow leaf curl virus (TYLCV), its construction method, and its applications. The method involves constructing a DNAβ promoter associated with a geminivirus expressed in the phloem into the RNAi vector pCambia1391, obtaining a 1391::DNAβpro vector backbone. RT-PCR is used to amplify a partial fragment of the whitefly key gene BtACTB, a key region of TYLCV (including the intergenic spacer region for viral replication initiation, some coat proteins, and replication-related proteins), and its inverted repeat sequences. This constructs a recombinant vector with an inverted hairpin structure driven by the phloem promoter, simultaneously targeting key sequences of both whitefly and TYLCV. The constructed recombinant vector is then introduced into tomatoes via Agrobacterium-mediated transformation. Screening yields tomato plants that reduce whitefly survival and inhibit TYLCV infection.

The application discloses a New Delhi tomato leaf curl virus coat protein polypeptide, antigen, antibody and application thereof, and belongs to the technical field of organism immunity detection. The application is based on ToLCNDV CP to design a polypeptide sequence, and provides a New Delhi tomato leaf curl virus coat protein polypeptide. The antigen prepared by coupling the polypeptide with keyhole limpet hemocyanin (KLH) can obtain a New Delhi tomato leaf curl virus antibody with high sensitivity and specificity, and can be used for screening the virus, and realizes instant detection and early warning of the ToLCNDV virus. Meanwhile, the application provides a theoretical basis and technical support for establishment of a virus serological diagnosis method and related detection product research and development, and is helpful to development of more accurate, efficient and portable detection products, so as to better serve the virus monitoring, quarantine and prevention and control work.

The invention belongs to the field of plant genetic engineering, and particularly relates to application of miR397 in enhancing virus resistance of corn, and the nucleotide sequence of the miR397 is shown as SEQ ID NO.24. The invention finds that the expression quantity of the miR397 is adjusted when SCMV and MCMV infect the corn, and the expression quantity of the miR397 is adjusted after SCMV or MCMV infection. The symptoms of the leaves or chlorotic mottles of corn leaves of transgenic overexpressed miR397 strains OE397-1 and OE397-2 are heavier, and the accumulation amount of virus RNA (Ribonucleic Acid) and coat protein is increased, while the symptoms of corn leaves of transgenic silent miR397 strains STTM397-10 and STTM397-11 are lighter, and the accumulation amount of virus RNA and coat protein is reduced. The results show that the miR397 can negatively regulate and control the virus resistance of the corn, so that the application of the miR397 in enhancing the virus resistance of the corn is provided.

The invention provides a nano-microsphere immunochromatography test strip for specifically detecting potato virus M. The test strip comprises a PVC (polyvinyl chloride) bottom plate, and a sample pad, a conjugate pad, an NC (nitrocellulose) membrane and a water absorption pad which are sequentially overlapped on the PVC bottom plate along a sample chromatography direction, a polystyrene nano-microsphere labeled antibody is fixed on the combination pad, a detection line T line and a quality control line C line are arranged on the NC membrane, a coated antibody is marked on the T line, and a goat anti-chicken antibody is marked on the C line; the labeled antibody and the coating antibody are paired monoclonal antibodies specifically combined with potato M virus coat protein PVM-CP; the labeled antibody is PVM-1G5B2F2 and is an IgG type antibody, the amino acid sequence of a heavy chain variable region is as shown in SEQ ID No.1, a light chain is a K type light chain, and the amino acid sequence of a light chain variable region is as shown in SEQ ID No.2. The test strip disclosed by the invention has the advantages of high sensitivity, high specificity, good stability, simplicity and rapidness in operation, high detection accuracy, wide application range and the like, and shows a good application prospect in rapid field detection of the potato virus M.

The present invention relates to a modified virus-like particle (VLP) of Cucumber Mosaic Virus (CMV) comprising at least one fusion protein, wherein the at least one fusion protein comprises or preferably consists of b) a chimeric CMV polypeptide, wherein the chimeric CMV polypeptide comprises or preferably consists of (iii) a CMV polypeptide, wherein the CMV polypeptide comprises a coat protein of CMV; and (iv) an antigen polypeptide, wherein the antigen polypeptide is inserted into the CMV polypeptide, wherein the insertion of the antigen polypeptide is between amino acid residues corresponding to position 84 and position 85 of SEQ ID NO: 62 of the CMV polypeptide; and (iii) a T helper cell epitope, wherein the T helper cell epitope replaces an N-terminal region of the CMV polypeptide, and wherein preferably the N-terminal region of the CMV polypeptide corresponds to amino acids 2-12 of SEQ ID NO: 62.

The invention relates to a primer group, a kit and a detection method for detecting a pepper virus F (BPVF), in particular to a primer group for detecting the pepper virus F (BPVF) and a kit for detecting the pepper virus F (BPVF). A primer group for loop-mediated isothermal amplification is designed according to a large coat protein (LCP) conserved region of a BPVF genome RNA2, the primer group consists of sequences 1, 2, 3, 4 and 5 in a sequence table, a complete loop-mediated isothermal amplification system is established, and the complete loop-mediated isothermal amplification system is combined with a colloidal gold test strip to realize visual detection. The method does not depend on precise instruments and equipment and professional operators, can complete detection only by a simple constant temperature device, has the characteristics of high reaction speed, high specificity, high sensitivity, rapid and visual result interpretation and the like, is suitable for pepper cutting stock plant screening, seedling quarantine and early detection of field infected plants, and has a wide application prospect. The method is suitable for popularization and application in seedling production units and disease monitoring departments.

The invention discloses a New Delhi tomato leaf curl virus coat protein polypeptide, an antigen, an antibody and application thereof, belongs to the technical field of organism immunodetection, and provides the New Delhi tomato leaf curl virus coat protein polypeptide based on design of a polypeptide sequence of ToLCNDV CP. The New Delhi tomato leaf curl virus antibody with relatively high sensitivity and specificity can be obtained through an antigen immune experiment body prepared by coupling the new Delhi tomato leaf curl virus antibody with KLH, and can be used for screening the virus, so that instant detection and early warning of the ToLCNDV virus are realized. Meanwhile, a theoretical basis and a technical support are provided for establishment of a virus serological diagnosis method and research and development of related detection products, and development of more accurate, efficient and portable detection products is facilitated, so that monitoring, quarantine and prevention and control work of viruses can be better served.

The application discloses application of glycoside compounds in prevention and treatment of plant pathogenic viruses and belongs to the technical field of pesticide antiviral agents.Taking a tobacco mosaic virus coat protein as an example, small molecules including sugar rings, such as Swertiamarin I (A0) and ZINC85593196 (B0), are screened through virtual screening, molecular dynamics simulation, molecular mechanics and MM / GBSA free energy calculation. Based on this, further optimization is carried out, and six compounds similar to the structure of A0, such as 4-methylumbelliferone-beta-D-xyloside (A1), gardenoside (A2), 4-methylumbelliferone-beta-D-pyranoside (A3), 4-methylumbelliferone-beta-D-pyranoglucoside (A4), catalpol (A5) and esculin (hemihydrate) (A6), are obtained, and in-vivo and in-vitro biological activity evaluation is carried out. The active ingredients screened by the above method have good inhibitory effect on plant viruses.

The application provides an adeno-associated virus mutant and application thereof, and the coat protein of the adeno-associated virus mutant comprises an amino acid sequence shown in SEQ ID NO: 1-5, or an amino acid sequence with more than 98% identity with SEQ ID NO: 1-5 and having the same or similar biological function. The application constructs an adeno-associated virus library by splicing and recombining a coat protein coding gene of a wild type adeno-associated virus, and obtains the adeno-associated virus mutant by screening with neutralizing antibodies against AAV coat proteins, the adeno-associated virus mutant has strong infection ability on human liver cells and can avoid the neutralization of neutralizing antibodies, and thus the technical obstacles existing in the field of hemophilia treatment are solved in a targeted manner.

The present invention relates to a modified virus-like particle (VLP) of Cucumber Mosaic Virus (CMV) comprising at least one fusion protein, wherein the at least one fusion protein comprises or preferably consists of b) a chimeric CMV polypeptide, wherein the chimeric CMV polypeptide comprises or preferably consists of (iii) a CMV polypeptide, wherein the CMV polypeptide comprises or preferably consists of a coat protein of CMV, wherein preferably the coat protein of CMV comprises or preferably consists of SEQ ID NO: 62; or an amino acid sequence having a sequence identity of at least 75%, preferably at least 80%, more preferably at least 85%, further preferably at least 90%, yet further preferably at least 95%, still further preferably at least 98% and yet still further more preferably at least 99% to SEQ ID NO: 62; and (iv) an antigen polypeptide, wherein the antigen polypeptide is inserted into the CMV polypeptide, wherein the insertion of the antigen polypeptide is between amino acid residues corresponding to amino acid residue of position 84 and position 85 of SEQ ID NO: 62 of the CMV polypeptide; and (iii) a T-helper cell epitope, wherein the T-helper cell epitope replaces an N-terminal region of the CMV polypeptide, and wherein preferably the N-terminal region of the CMV polypeptide corresponds to amino acids 2-12 of SEQ ID NO: 62.

This invention discloses a hybridoma cell line secreting monoclonal antibody PVY-2, its monoclonal antibody, and its applications. The hybridoma cell line 4F1B2G11 secretes a monoclonal antibody against potato virus Y. The preservation number of the hybridoma cell line is CCTCC NO: C2022281. The monoclonal antibody PVY-2 has a specific immunoreactivity with the coat protein of potato virus Y. The nucleotide sequence of the heavy chain variable region of monoclonal antibody PVY-2 is shown in SEQ ID NO.4, and the nucleotide sequence of the light chain variable region is shown in SEQ ID NO.5. The sensitivity of the direct ELISA method for detecting potato virus Y-infected leaves reaches a 1:5120 dilution. The monoclonal antibody PVY-2 can also be used to prepare ELISA kits, colloidal gold kits, or nano-enzyme kits, enabling rapid, sensitive, economical, and accurate detection of potato virus Y disease.

The present disclosure relates to a single stranded RNA vector suitable for introducing a therapeutic agent, such as a peptide, a protein or a small RNA, into a host plant. The vector does not encode for any movement protein or coat protein, but is capable of systemic and phloem-limited movement and replication within the host plant.

The application relates to a method for extracting bacteriophage nucleic acid based on a centrifugal column method, which comprises the steps of urea lysis, denaturation, adsorption, rinsing and the like. The technical principle of the application is that high-concentration urea can be used to denature and purify by breaking the inclusion body structure, urea-containing denaturation lysis solution is used to destroy the bacteriophage coat protein to expose the internal nucleic acid, and the bacteriophage nucleic acid is extracted based on the centrifugal column method. Compared with a commercial virus nucleic acid extraction kit, the method has the advantages of simplicity, high efficiency, economy and convenience, and the nucleic acid extraction can be completed within 45 minutes.