71 results about "Polyhedrin" patented technology

The invention relates to a porcine circovirus type 2 subunit vaccine, and a preparation method and an application thereof. The recombinant baculovirus contains double promoters (a polyhedrin protein promoter and a P10 promoter), and can express double copies of Cap protein coding genes, such that protein expression efficiency is substantially improved. Also, Cap protein expressed by an inserted exogenous gene does not contain excess sequences, such that virus-like particles (VLPs) can be effectively formed, expressed protein immunogenicity is improved, and the content of produced antigen is high. According to the porcine circovirus type 2 subunit vaccine provided by the invention, protein yield and quality of porcine circovirus type 2 subunit vaccine are substantially improved, and prepared vaccine compositions have the advantages of stable and long-lasting immune effect, high safety, and the like.

The invention discloses a direct PCR detection method of Bombyx mori nuclear polyhedrosis pathogeny BmNPV, comprising the following steps of: firstly, treating the blood of infected Bombyx mori by ethanol precipitation to remove a PCR reaction inhibitor; designing the PCR primer of a polyhedrin gene according to the genome analysis of the Bombyx mori nuclear polyhedrosis pathogeny BmNPV; carrying out PCR amplification on the polyhedrin gene, adding an anti-PCR reaction inhibitor BSA (Bull Serum Albumin) to a reaction system and simultaneously carrying out PCR reaction by the primer of a Bombyx mori chondriosome CO I gene to make positive control; respectively getting the blood of normal Bombyx mori and the inflected midguts of the Bombyx mori infected with white muscardine, green muscardine, a bacterial disease and a microsporidia disease and then carrying out PCR reaction specification analysis; and detecting the PCR reaction result by agar gel electrophoresis. The whole detection process has simple operation and can be completed only by 4 hours. The disease can be diagnosed at the early stage of BmNPV infection by adopting the direct PCR detection method to carry out periodical sampling detection so as to adopt a measure in time to prevent the disease from happening.

The invention discloses a dual-host recombination rhabdovirus expression vector and a construction method and application thereof, belonging to the technical field of gene engineering. The dual-host recombination rhabdovirus expression vector is provided with a recognizable Polyhedrin promoter of an insect cell and a recognizable CMV-IE promoter of an animal cell. Dual-host recombination rhabdovirus can be used for preparing a functional protein on the insect cell or can express a target foreign protein on the animal cell and can be used for gene therapy and nonreplication vector vaccine. The construction method of the dual-host recombination rhabdovirus expression vector comprises the following steps of: taking a transfer vector pFas in a Bac-to-Bac expression system as a base; introducing a CMV-IE promoter expression kit on the upstream of the Polyhedrin promoter; constructing the transfer vector; transforming a DH10Bac competent cell; recombining a dual-host Bacmid shuttle vector; and then transfecting insect cells in a logarithmic phase to obtain the dual-host recombination rhabdovirus expression vector.

The invention relates to the technology of antigen protein expression, and particularly relates to a method for preparing a cyprini herpesvirus II antigen coated polyhedrosis based on a baculovirus expression system. According to the method, by designing and recombining bombyx mori nuclear polyhydrosis virus BmNPV-VP3-cyHV-polh, 1-186, 993-1197, 603-783 and 85-186 regional sequences of ORF72, ORF66, ORF81 and ORF82 and the coding sequence of the 1-279 region of a VP3 gene of bombyx mori cytoplasmic polyhedrosis virus structural protein are connected in series to form a fused sequence which is controlled by baculovirus P10 promoter; and the bombyx mori cytoplasmic polyhedrosis protein gene is controlled by a polyhedrin gene promoter of baculovirus. The virus is used for inoculating bombyx mori or bombyx mori culture cells, the recombinant virus expressed cyprini herpesvirus II antigen protein can be coated in bombyx mori cytoplasmic polyhedrosis; the formed polyhedrosis can be purified by simple differential centrifugation; the purified polyhedrosis is cracked under a basic condition, the polyhedrosis protein can be precipitated by centrifuging, and the cyprini herpesvirus II antigen is reserved in supernatant, so that the cyprini herpesvirus II antigen can be quickly and conveniently obtained.

The invention relates to a method for preparing platinum nanowires through helicoverpa armigera nuclear polyhedron extractives. The method mainly includes the steps that after centrifugal purification is carried out on helicoverpa armigera nuclear polyhedrosis virus raw powder, resuspension with ultrapure water is carried out, alkaline hydrolysis liquid is added for processing, chloroform is added for even shocking, supernate is taken for overspeed centrifugation, ultrapure water is added for dissolving sediment spots, and then the polyhedrin extractives are obtained; a K2PtC16 solution is added into the obtained extractives, sufficient and even mixing is carried out, hatching is carried out in an air bath table at the indoor temperature for 20 h-50 h, a NaOH solution is used for adjusting the pH value to range from 7 to 9, and hatching is continuously carried out for 20 h to 50 h; a NaBH4 solution is added for reduction, and the platinum nanowires with net structures are obtained. The simple and environmentally-friendly platinum nanowire synthetic method which is even in structure and shape distribution, adjustable is size and better in stability is provided, and the prepared net-shaped platinum nanowires are even in shape and stable in structure and have the good potential application value on the aspects of fuel cell, biosensing, organocatalysis and the like.

Cypoviruses and baculoviruses are notoriously difficult to eradicate because the virus particles are embedded in micron-sized protein crystals called polyhedra. The remarkable stability of polyhedra means that like bacterial spores these insect viruses remain infectious for years in soil. Although these unique in vivo protein crystals have been extensively characterized since the early 1900s, their atomic organization remains elusive. Here we describe the 2 crystal structure of both recombinant and infectious silkworm cypovirus polyhedra determined using 5-12 micron crystals purified from insect cells. These are the smallest crystals yet used for de novo X-ray protein structure determination. It was found that polyhedra are made of trimers of the viral polyhedrin protein and contain nucleotides. Although the shape of these building blocks is reminiscent of some capsid trimers, polyhedrin has a new fold and has evolved to assemble in vivo into 3-D cubic crystals rather than icosahedral shells. The polyhedrin trimers are extensively cross-linked in polyhedra by non-covalent interactions and pack with an exquisite molecular complementarity similar to that of antigen-antibody complexes. The resulting ultra-stable and sealed crystals shield the virus particles from environmental damage. The structure suggests that polyhedra can serve as the basis for the development of robust and versatile nanoparticles for biotechnological applications such as in cell culture systems, microarrays and biopesticides.

Insect-derived promoters for foreign proteins expression in insect cells. Regulatory polynucleotide sequences which drive the expression of major insect proteins (hexamerins) at specific evolution stages of larva have been isolated from insects (Trichoplusia ni) in the present invention. Said regulatory polynucleotide sequences promote stronger foreign gene expression in the baculovirus system than the conventional polyhedrin promoter. Additionally, the combination of the new larva-derived promoters of the invention with the pL promoter increased baculovirus expression levels up to 61%-375% (depending on the time of infection) with respect to conventional baculo viruses used in the biotechnology industry. Promoter pB2 also drives gene expression at earlier times than polyhedrin promoter, being this feature a great advantage for correct protein folding and posttranslational modification.

Provided is an insect control sheet using a polyhedrin protein polyhedron (Cry polyhedron) in which the insecticidal protein (Cry toxin) produced by Bacillus thuringiensis is fixed. The insect control sheet contains the Cry polyhedron, and is used by floating on water. The insect control sheet floats on the surface of water, and is obtained by layering a pure matrix layer (20) and a toxin-containing matrix layer (30) containing a Cry polyhedron (51) onto the undersurface of a sheet-shaped first sheet substrate (10). The pure matrix layer (20) comprises an easily decomposable or water-soluble second material, while the toxin-containing matrix layer (30) comprises the Cry polyhedron and an easily decomposable or water-soluble third material. The Cry polyhedron is gradually released from the toxin-containing matrix layer into the water on which the control sheet is floating.

The invention relates to a recombinant virus and method for producing L-asparaginase II by using the virus, which belong to the technical field of bioscience. The invention has the purpose of providing the recombinant virus. The virus comprises a polyhedrin gene and an L-asparaginase II gene. Therefore, the recombinant virus is transferred to a silkworm to produce the L-asparaginase II connected with the polyhedron by a covalent bond; and then the L-asparaginase II is separated and purified by a polyhedral body; the recombinant virus has the characteristic of high expression level in the silkworm body; and the L-asparaginase II separated and purified by the polyhedral body has the characteristic of high purity.

An insect control sheet containing a Cry polyhedron prepared by fixing an insecticidal protein (a Cry toxin) produced by Bacillus thuringiensis to a polyhedron of polyhedrin protein is provided. The insect control sheet contains the Cry polyhedron and is used by floating on water. The insect control sheet is floatable on water, and includes a pure matrix layer 20 and a toxin-containing matrix layer 30 containing the Cry polyhedron 51 which are layered on the underside of a sheet-shaped first sheet substrate 10. The pure matrix layer 20 is composed of a degradable or water-soluble second material and the toxin-containing matrix layer 30 is composed of a degradable or water-soluble third material and the Cry polyhedron. The toxin-containing matrix layer sustainably releases the Cry polyhedron to the water on which the insect control sheet is floated.

The invention relates to an animal genetic engineering interferon compound preparation, the production method and the clinical application. The animal genetic engineering interferon compound preparation is prepared by extracting the animal peripheral blood or spleen lymphocytes, culturing, inducing by in vitro inductor, extracting the cell total RNA by Trizol, designing the specific primer, cloning the interferon gene by RT-PCR technology and connecting to the pGEM-T carrier by T-A strategy; the primer is designed again, the both ends are added with different restriction endonucleases digestion sequences, initiation codon ATG and termination codon TAA, leading peptide sequences are removed, the PCR amplification is carried out by taking the recombination T carrier as the template, so as to obtain the expression fragment of the animal interferon gene; the expression fragment is carried out with the rare codon mutation, and gel recovery target fragment is connected on the carrier of pFastBacDual with the same double restriction endonucleases digestion after double restriction endonucleases digestion; the interferon-Alpha of an animal is cloned to multiple cloning sites under the control of Polyhedrin promoter, the interferon-Gamma of the same species animal is cloned to multiple cloning sites under the control of p10 promoter; the constructed carrier of pFastBacDual plus interferon Alpha plus interferon Gamma are transfected to DH10BacE.coli to carry out recombination; the constructed recombinant bacmid is extracted and purified after the blue white screening and the PCR identification, and the transfection of SF9 insect cell is carried out by a liposome method; the expression product is carried out with identification and purification; the animal genetic engineering interferon compound preparation is carried out with anti-virus activity detection and the evaluation of the clinical application effects.