249 results about "Genetic recombination" patented technology

The invention relates to improved methods for directed evolution of polymers, including directed evolution of nucleic acids and proteins. Specifically, the methods of the invention include analytical methods for identifying "crossover locations" in a polymer. Crossovers at these locations are less likely to disrupt desirable properties of the protein, such as stability or functionality. The invention further provides improved methods for directed evolution wherein the polymer is selectively recombined at the identified "crossover locations". Crossover disruption profiles can be used to identify preferred crossover locations. Structural domains of a biopolymer can also be identified and analyzed, and domains can be organized into schema. Schema disruption profiles can be calculated, for example based on conformational energy or interatomic distances, and these can be used to identify preferred or candidate crossover locations. Computer systems for implementing analytical methods of the invention are also provided.

The invention discloses humanized genetic recombinant human-like collagen produced by eukaryotic bacteria. The humanized genetic recombinant human-like collagen has amino acid with the total length of 474, and is formed by connecting two sections of completely-identical human III-type collagen sections in series; the end C is connected with six histidine residue groups serving as specificity affinity purification markers. The performance of the genetic recombination human-like collagen is superior to animal collagens and original nuclear engineering bacteria recombinant collagens; and with the specificity affinity purification markers, the high-purity product is easily acquired.

The invention concerns a purified recombinant glycoprotein having the following properties: a) an adherence capacity to CD4; b) an affinity with a anti-gp120 antibody capable of neutralizing in vitro HIV cell infection; c) an affinity with an anti-gp41 antibody; d) a timeric form free from inter-chain disulphide bonds. The invention also concerns a vaccine comprising said purified glycoprotein and an adjuvant. The invention further concerns a method for obtaining said glycoprotein, which consists in expressing, by means of genetic recombining techniques, a glycoprotein corresponding to the properties a), b) and c) mentioned above; purifying it, and subjecting it to steps involving at least a reducing agent, an ionic detergent and/or a neutral detergent in conditions leading to a glycoprotein having said properties.

The invention discloses a traceless modification method of bacillus subtilis genome. The method disclosed by the invention is used for carrying out traceless modification on the bacillus subtilis genome by utilizing an upp positive-negative selection system. The method disclosed by the invention utilizes a ComK expression system, so that the bacillus subtilis has an excellent dsDNA (double-stranded deoxyribonucleic acid) conversion efficiency which can be up to 3-5*10<3>cfu/microgram dsDNA. Meanwhile, an exogenous endonuclease I-SceI expression system is utilized to bring double-stranded DNA breakage into the genome, so that the genetic recombination efficiency in negative selection molecules is obviously improved and can be up to 8*10<-4>. According to the method disclosed by the invention, iterative modification can be performed on a plurality of target nucleotide sequences in the bacillus subtilis genome, and the steps of introducing gene mutation to the genome, knocking out target gene sequences from the genome, deleting a large fragment of genomic sequences and the like are included.

The invention provides methods of modifying the level of expression or functional activity of factors such as enzymes or other catalytic proteins or structural proteins, alone or in concert, to modify the frequency of meiotic homologous recombination involving the exchange of genetic information between non-sister chromatids from homologous maternal and paternal chromosomes. The steps at which modulation may occur include: homologous chromosome pairing, double-strand break formation; resection; strand invasion; branch migration; and resolution. Methods of plant and animal breeding are also provided that utilize the modulation of meiotic homologous recombination.

The present invention relates to a pharmaceutical composition for inhibiting angiogenesis which comprises arginine deiminase as an active ingredient, where the arginine deiminase, obtained from Mycoplasma arginini or prepared by a genetic recombination technique, may be conjugated to an activated polymer to lower its immunogenecity and increase its life time. The pharmaceutical composition of the present invention exhibits an excellent inhibitory activity against angiogenesis.

The invention discloses application of erythropoietin microspheres to preparation of drugs for treating motor complications in the Parkinson's disease. The erythropoietin microspheres are obtained by means of preparing one of naturally extracted erythropoietin, genetic recombination expression erythropoietin, polyethylene glycol modified erythropoietin, glycosylation modified erythropoietin or human serum fused erythropoietin with polysaccharides into particles, and preparing the particles with sustained-release materials into the microspheres. The application has the advantages that a novel medicinal use of the erythropoietin microspheres is cultivated, a novel application field is developed, treating and preventing the motor complications in the Parkinson's disease by the erythropoietin microspheres have the advantages of long-acting sustained release, no toxic and side effects, fine compliance, patient pain relieving, low cost and the like and are easily accepted by patients, and the erythropoietin microspheres are simple in preparation process and environment-friendly and have excellent application prospects in treating and preventing the motor complications in the Parkinson's disease.

The invention provides a preparation method of a double chimeric antigen receptor gene modified T lymphocyte targeting breast cancer stem cells. The preparation method is characterized in that integrin-associated protein (CD47) and transcriptional coactivator (TAZ) are both highly expressed in breast cancer tissues, especially in the breast cancer stem cells; by established CD47 and TAZ over-expressed breast cancer cells, higher proliferation and metastasis capacity and cancer stem cell features are shown. Extracellular domain of the two breast cancer stem cell antigens CD47 and TAZ are targeted to generate monoclonal strains in specific binding under immunity action, and single-chain antibodies in specific binding with the CD47 and TAZ by genetic recombination are obtained to construct a human CD47 and TAZ containing double chimeric antigen receptor gene recombined to a virus vector to transfect human T lymphocyte. By high expression of the double chimeric antigen receptor gene in specific binding with human CD47 and TAZ expressing breast cancer stem cells, a first signal and a costimulatory signal can be activated to trigger anti-breast-cancer cytotoxicity, and high cytotoxicity in in-vivo and in-vitro anti-cancer experiments is achieved.

The invention relates to the field of genetic engineering, in particular to preparation of an infectious clone vector of a Pepper mild mottle virus (PMMoV) of RNA (ribonucleic acid) plant viruses and tobacco mosaic viruses, pathogenesis analysis on an infectiously cloned agrobacterium tumefaciens strain with the pepper mild mottle virus and exogenous proteins infectiously cloned and expressed by the aid of the PMMoV. The preparation, the pathogenesis analysis and exogenous proteins have the advantages that genomes of Shanghai bay isolate of the pepper mild mottle virus are constructed onto efficient plant expression vectors pCB301-CH by the aid of a genetic recombination process, the recombinant vectors are transferred into the agrobacterium tumefaciens strain by means of electroporation, and accordingly the virus vector with infection ability can be obtained; the plant expression vectors can be constructed by means of infectious cloning, and the exogenous proteins can be efficiently and stably expressed in host plants; mature systems can be provided for studying structures and functions of the virus genomes and studying interaction between the virus and hosts.

The invention relates to the field of plant virus gene engineering and provides a construction and an application of a tobacco vein banding mosaic virus infectious clone. A genome of a tobacco vein banding mosaic virus HN39 isolate is cloned to the downstream part of a 35S promoter in a genetic recombination mode, and the infectious clone with strong infectivity is obtained. A plant expression vector can be constructed by utilizing the infectious clone and used for stably and efficiently expressing extrinsic protein in a host plant body, and the infectious clone can be also modified into a low virulent strain for protecting a plant from being infected with a high virulent strain.

According to the present invention, a technique of increasing the frequency of genetic recombination in genomic DNA of a plant is established. Such technique comprises: introducing a restriction enzyme gene that can be expressed in a target plant cell into the plant cell and causing the restriction enzyme gene to be transiently expressed so as to induce genetic recombination of genomic DNA; or introducing a promoter and a restriction enzyme gene using the Agrobacterium method so as to induce genetic recombination of genomic DNA.

The invention discloses gene recombination mediated on the basis of phiC312 and inheritance reformation for an erythrocin producing bacterium. A target gene can be stably integrated on a locus pre-constructed by a host cell genome by a method of gene recombination mediated by a phiC312 locus specificity integration mechanism. The invention also relates to an application of the method on the inheritance reformation of the erythrocin producing bacterium.

The invention relates to an inducible inheritance recombinase system CrexER. The CrexER is a fusion protein; the fusion protein is a protein formed by fusing recombinase Cre, estrogen receptors ER andrecombination sites rox specifically recognized by recombinase Dre. The invention also provides a coding sequence of the fusion protein, a nucleic acid construct containing the coding sequence, a host cell and the like. The ahead occurrence of Dre-rox homologous recombination is used for inducing the subsequent occurrence of Cre-loxP homologous recombination; the targeted operation of the A-Dre and B-Cre mark cell intersection (A+B+) is realized. The application range of the inheritance targeted operation is greatly expanded; a precious strategy is provided for the precise inheritance targeted operation and biomedical research.

The present invention relates to a method for increasing genetic recombination frequency in a genomic DNA and a method for inducing genome rearrangement. Specifically, according to the present invention there are provided: the method for increasing genetic recombination frequency in a cell in which genetic recombination takes place at any sites in the genome, comprising causing a restriction enzyme to be expressed in the cell, inducing transient activation of the restriction enzyme, and then introducing 2 or more double strand cleavages into any genomic DNA of the cell, so as to increase the genetic recombination frequency; the method for inducing genome rearrangement through the use of the above method; and cells each prepared through the use of the above 2 methods.

The invention discloses genetic recombinant collagen-like peptide MJLGG-34 as well as a preparation method and application thereof, and belongs to the technical field of genetic engineering. Comparedwith the traditional natural collagen, the collagen-like peptide MJLGG-34 obtained through genetic recombination has the advantages that the collagen-like peptide MJLGG-34 is small in molecular weight, easy to prepare and stable biological activity, has better transdermal rate and higher biological activity, and is more easily absorbed by skin while guaranteeing the biological activity; the collagen-like peptide MJLGG-34 is good in biocompatibility and biology safety, has excellent biological activity, such as oxidation resistance, apoptosis resistance and melanogenesis inhibiting, can obviously inhibit oxidative damage of skin, regulate melanogenesis and resist ageing, and does not have obvious toxic or side effects; the collagen-like peptide MJLGG-34 can be applied to food, health care products and cosmetics, and is wide in application range, thereby having the excellent application value and industrial prospect. The preparation method is simple, high in production efficiency, low inproduction cost and wide in application prospect.

The invention provides an anti-ageing gene oligopeptide-containing preparation and an application of the preparation to cosmetics. The preparation is prepared by compounding gene oligopeptide key components, auxiliary materials and preparation raw materials. Gene oligopeptide is selected from one or a combination of genetic recombination hydrolyzed collagen dipeptide, genetic recombination hydrolyzed collagen tripeptide, genetic recombination hydrolyzed collagen tetrapeptide, genetic recombination hydrolyzed collagen pentapeptide, genetic recombination hydrolyzed collagen hexapeptide, first genetic recombination hydrolyzed collagen, second genetic recombination hydrolyzed collagen, third genetic recombination hydrolyzed collagen, genetic recombination gene protein, first genetic recombination hydrolyzed hyaluronic acid and second genetic recombination hydrolyzed hyaluronic acid.

The invention discloses a cultivating and planting method of strong gluten wheat. The cultivating and planting method comprises the following steps of: selecting biparental Suzhou wheat VI and intermediate strain yang 97G59 with excellent characters; and creating transgression descendant by utilizing genetic recombination and an additive effect, so that the novel wheat strain zhen 02168 which is excellent in gluten, large in grain, good in comprehensive resistance, stalked and lodging-resistant, delicately grown, good in later-stage coloring and good in ripe phase. The novel wheat strain cultivated by the cultivating and planting method disclosed by the invention is full in seed and red in skin, hard and good in fullness, and is the novel wheat strain with the seed quality reaching the quality gluten standards, which firstly passes examination and approval of China and Jiangsu province in Huainan wheat region of Jiangsu. Moreover, the strong gluten wheat has the advantages of being good in ripe phase, high in yield and strong in stress resistance. Besides, the wheat strain is invented for solving a big problem in the Huainan wheat region of Jiangsu, and strong in practical value.

The invention relates to the field of molecular biology and immunology, in particular to an application of an HBcAg (hepatitis B core antigen) virus-like particle serving as a cervical cancer therapeutic vaccine carrier. A preparation method comprises steps as follows: an HPV16 E749-57CTLs epitope peptide fragment is selected, a DNA (deoxyribose nucleic acid ) fragment of the HPV16 E749-57CTLs epitope peptide fragment is inserted between 78 and 79 amino acids of the HBcAg through genetic recombination, an obtained recombinant plasmid pHBcAg-E749-57 is converted into Escherichia coli DH5alpha, and an HBcAg virus-like particle vaccine presenting E749-57 is obtained after induction expression and purification. After a tumor-bearing mouse is immunized with the virus-like particle vaccine, the body of the mouse can be induced to generate a higher HPV16E7 specific cellular immunologic response, and growth of tumors is remarkably inhibited.