60 results about "Cellular Transformation" patented technology

The invention discloses a method for producing alpha-ketoisocaproate by whole-cell transformation, belonging to the field of fermentation engineering. The method comprises the steps of firstly, constructing a genetically engineered bacterium of a heterologous expression amino acid deaminase gene, taking leucine as a substrate and producing the alpha-ketoisocaproate by whole-cell catalysis through a recombinant strain. The method has the advantages of being low in production cost, mild in production conditions, less in impurities in a transformation system, simple in processing steps, safe in production operation, etc. The alpha-ketoisocaproate produced by the method is high in yield, the transformed liquid per liter contains 12.69g of alpha-ketoisocaproate, and the conversion rate of L-leucine reaches 97.49%.

The invention discloses a method for preparing levodopa by virtue of an enzymic method. The method comprises the following steps: picking up an annular stenotrophomonas maltophilia strain slant for inoculation into a seed culture medium for culturing, thereby obtaining a primary seed liquid; inoculating a fermentation culture medium with the primary seed liquid at the inoculum size of 3-10% for fermentation culturing, centrifuging after the fermentation is ended and collecting bacterial cells; and adding tyrosine and the bacterial cells to a buffer solution to have an enzymatic reaction under the conditions of 18-30 DEG C and the pH of 5.0-6.0, thereby converting the tyrosine into the levodopa. According to the method, due to the resting cell transformation technology, and the preferred intermittent weak ventilation technology, adopted in the transformation process, the catalytic efficiency of the enzyme is improved; the concentration of the levodopa is 27g/L and the molar transformation rate of the tyrosine is above 99%; and besides, the method is mild in conditions, high in enantio-selectivity and free from racemization effect, is more suitable for industrial production, and has remarkable economic benefit and industrial application value.

The invention discloses escherichia coli expressing thermostable tyrosine phenolase and application thereof, and belongs to the technical field of bioengineering. According to the invention, escherichia coli BL21 is taken as a host, recombinant plasmids pET-28(a)-TPL and 25 tyrosine phenolase mutants are expressed, recombinant escherichia coli containing mutant plasmids for producing L-DOPA is obtained, whole-cell transformation is carried out on the obtained recombinant bacteria to produce the L-DOPA, the yield of the L-DOPA produced by the recombinant bacteria expressing the pET-28(a)-TPL (E313M) reaches 54.9 g/L, compared with a control strain, the yield increases by 142.9%, the half-life period of the expressed tyrosine phenolase is improved to 37.9 min, 17.1 min and 14.6 min respectively under the conditions of 20 DEG C, 40 DEG C and 60 DEG C. The escherichia coli lays the foundation for the L-DOPA production by the escherichia coli modified by metabolic engineering.

The invention relates to a method for preparing alpha-aminobutyric acid by utilizing series connection amino acid dehydrogenase and codon optimization formate dehydrogenase recombinant escherichia coli. First, codon optimization is performed on a Candida boidinii formate dehydrogenase gene sequence according to the codon preference of the escherichia coli. After codon optimization on formate dehydrogenase, the expression quantity of formate dehydrogenase in the escherichia coli can be improved remarkably, the yield of alpha-aminobutyric acid is increased, and in the escherichia coli, co-expression formate dehydrogenase and L-amino acid dehydrogenase can promote circulation of cofactors in mycetome without needing the adding of any exogenous cofactors. In addition, the process of utilizing whole-cell transformation bulk chemical L-threonine to produce alpha-aminobutyric acid is simple and quick, and the cost is low. In a 5 L fermentation tank, the yield of alpha-aminobutyric acid obtained through the method can be 81.5 g/L, and an actually effective strategy is provided for industrial production of alpha-aminobutyric acid.

The invention discloses a method for improving production efficiency of D-tyrosine, which belongs to the technical field of bioengineering. A double-plasmid co-expression recombinant bacterium is constructed through a molecular biological means, efficient expression of three enzymes is achieved at the same time, L-tyrosine is converted into D-tyrosine, NADP<+> is converted into NADPH through a coupling coenzyme regeneration system, and NADPH cyclic regeneration and conversion can be efficiently conducted, the efficient production of D-tyrosine is realized by optimizing whole-cell transformation conditions. The yield of the D-tyrosine produced by the method can reach 8.4 g/L, and the conversion rate reaches 93%.

The invention discloses a method for realizing whole cell transformation to synthesize L-phenyllactic acid by a genetic engineering strain, in particular to a genetic engineering strain capable of co-expressing phenylalanine dehydrogenase and L-hydroxyisocaproic acid reductase to realize self-circulation of cofactors NAD<+> and NADH. The method for synthesizing L-phenyllactic acid by a whole celltransformation substrate L-phenylalanine belongs to the field of bioengineering technology. By using the whole cell transformation of a recombinant strain E.coli BL21(DE3)/pET28a-pdh-ldh to synthesizeL-phenyllactic acid, the whole cell transformation rate can reach 88.9% to 95.6% under the action of an added surfactant. By adopting the method, the self-circulation of the cofactors NAD<+> and NADHis realized, the addition amount of the cofactors is reduced, the production cost is reduced, and the method has a broad application prospect in the field of industrial synthesis of L-phenyllactic acid.

The present invention relates to a vaccine comprising a particle, said particle comprising (i) at least one Epstein-Barr virus (EBV) structural polypeptide, (ii) at least one EBV lytic polypeptide, (iii) membrane lipids, said particle being devoid of EBV DNA, wherein (a) the B-cell transformation capacity of one or more EBV polypeptides required for B-cell transformation as comprised in said particle is disabled while their immunogenicity is maintained; and/or (b) said particle is devoid of one or more EBV polypeptides required for B-cell transformation. Furthermore, the invention relates to a method for generating a particle, to a cell obtained in the method of the invention, a kit comprising the vaccine or the particle generated according to the method of the invention. Also, the invention relates to the use of the vaccine or the particle generated according to the method of the invention for generating CD8+ cells specific for an EBV antigen.

The invention relates to an anti-human papilloma virus small-molecular antibody as well as a composition, a preparation method and application thereof. The anti-human papilloma virus small-molecular antibody Fab can enter an infected cell through a cell membrane to attack an HPV-E6/E7 oncogene protein, and paralyze and inactivate the HPV-E6/E7 oncogene protein to cause the protein to lose cell transformation and carcinogenesis. According to the anti-human papilloma virus small-molecular antibody disclosed by the invention, anti-human papilloma virus E6, E7and E6/E7 small-molecular antibodies Fab of different combinations for covering all locally popular types of HPVs can be produced according to an epidemic situation of local HPV, so as to take objective-oriented measures and realize precise prevention and treatment. The invention further provides a liquid crystal micro capsule, gel, a suppository, ointment, lotion, a tablet, an effervescent tablet, a capsule, a soft capsule, a spray and an injection which are prepared from the anti-human papilloma virus small-molecular antibody and the composition thereof. The anti-human papilloma virus small-molecular antibody is used for preventing and treating human papilloma virus (HPV) infection and/or applied to a drug, a disinfection product, a health care product and a medical instrument for preventing and treating the cervical cancer.

The invention relates to the technical field of biology, and in particular to a method for synthesizing D-psicose by using the whole cell transformation. In the method, the entire reaction system comprises a substrate D-fructose, wet bacteria of recombinant Escherichia coli after induction, ATP and metal ions, the reaction system is subjected to a catalytic reaction and then is heated, cooling isperformed and then acid phosphatase is added to carry out a dephosphorylation reaction to obtain D-psicose. The yield of D-psicose can be improved by using the method.

The invention relates to an immortalized quality-control cell bank for chromosome karyotype analysis in the medicine field and a construction method thereof. The invention is mainly characterized in that the construction method comprises: taking residual attached primary or sub-culture living cells which are used for chromosomal disease diagnosis as needed by clinical diagnosis and treatment and are definitely diagnosed to have difficult chromosome abnormalities, introducing, through transgenosis technology, SV40LTag-pcDNA3.1(-) recombinant plasmid constructed by pcDNA3.1(-) connected by T4DNA ligase and digested by BamHI, and SV40LTag DNA amplified by PCR and separated by agarose gel electrophoresis, allowing recon to integrate with the cell DNA, screening immortalized cells integrated with recons by G418, performing subculture amplification and living cell cryopreservation, then extracting several respectively-prepared cells with different diseases, mixing the cells according to a required ratio for quality control so as to convert each original cell with a single chromosome abnormality into a cell with a plurality of easy-to-misdiagnose chromosome abnormalities with different ratios. Therefore, the difficulty and complexity for differential diagnosis and chromosome chimera diagnosis are increased; samples are easily available; and waste residual cells are converted into effective quality-control materials.

The invention relates to lycoris plant lycoris aurea 1-aminocyclopropane-1-carboxylic acid synthetase as well as a coding gene and application thereof. The lycoris plant lycoris aurea 1-aminocyclopropane-1-carboxylic acid synthetase is disclosed for the first time, and has good enzymatic activity and can catalyze adenosyl methionine to synthesize the 1-aminocyclopropane-1-carboxylic acid. The invention also discloses a polynucleotide for coding the 1-aminocyclopropane-1-carboxylic acid synthetase, a vector and a host cell for expressing the 1-aminocyclopropane-1-carboxylic acid synthetase, and a method for producing the 1-aminocyclopropane-1-carboxylic acid by using a whole-cell transformation method.

The invention discloses a method for preparing hydrocortisone by resting cell multi-round fermentation. The method comprises the following steps: by taking vitiligo blue as a production strain, carrying out seed amplification culture, adding a substrate RSA into fermentation liquor, and performing converting to generate hydrocortisone; after transformation is finished, collecting mycelia centrifugally, taking water as a fermentation medium to feed a substrate RSA for fermentation transformation, and so on, performing multiple rounds of resting cell transformation. Particularly, in the resting cell multi-round transformation process, transformation medium water only needs to be simply boiled, high temperature, high pressure, any PH adjustment and other aspects like culture medium sterilization are not needed, the strain culture step is omitted, materials and power needed by preparation and sterilization of the culture medium are also saved, and the production cost is reduced; and the conversion rate and the specific productivity of hydrocortisone are improved.

The invention discloses a method for producing 1, 4-butanediamine by using recombinant escherichia coli, which belongs to the genetic engineering technology, and is characterized in that an arginine decarboxylase mutant and agmatine enzyme are successfully expressed by using a high-copy plasmid pXMJ19 to construct recombinant bacteria. Whole-cell transformation results show that the original bacteria do not have the capability of excessively accumulating 1, 4-butanediamine, and the recombinant bacteria can realize excessive accumulation of 1, 4-butanediamine; and meanwhile, based on the characteristic that the genetically engineered strain can excessively accumulate 1, 4-butanediamine, enzymatic conversion is successfully adopted to produce 1, 4-butanediamine by taking arginine as a substrate. IPTG (isopropyl-beta-d-thiogalactoside) is added in a cell culture process to induce enzyme expression, and magnesium ions and coenzyme pyridoxal phosphate are added in a transformation system according to enzymatic properties of the arginine decarboxylase. Finally, 72.6 g.L <-1 > 1, 4-butanediamine can be accumulated through 24-hour conversion, and the yield of agmatine serving as an intermediate product is 0.14 g/L.

The present disclosure relates to suppression of cellular transformation and dysplasia by topical application of Lefty. In particular, the present disclosure provides compositions and methods for topically applying Lefty to treat and prevent cancers.

A kit is used for diagnosing NPM1 antibodies, ranilla luciferase genes and NPM1 antigen genes are recombined into fusion vectors, and through a cell transformation technology, the fusion vectors are guided into a mammalian cell system to conduct luciferase-NPM1 antigen fusion protein expression; gene recombination cells are disrupted, luciferase-NPM1 antigen fusion proteins are obtained, NPM1 antigens are coated with a 96 elisa plate, and to-be-detected serum is added; the antibodies in the serum are combined with the antigens on the plate to be adsorbed to the plate; and the luciferase-NPM1 antigen fusion proteins are added, through an immunoprecipitation reaction, the luciferase-NPM1 antigen fusion proteins are combined with the NPM1 antibodies in the serum of a patient and are adsorbedto the plate, and finally a luciferase substrate is added to detect the fluorescence intensity. According to the fluorescence intensity, the content of the NPM1 antibodies can be reflected to providereference for diagnosis of prostatic cancer; and a method is quick, simple and convenient and has high sensitivity.

The invention discloses a method for transforming and producing 9-OH-AD by using whole cells of recombinant corynebacterium glutamicum, and belongs to the technical field of bioengineering and biology. Through a shuttle plasmid pXMJ19 between escherichia coli and corynebacterium glutamicum, an oxidization subunit KshA and a reducing subunit KshB of 3-ketosteroid 9alpha-hydroxylase from Mycobacterium sp.Strain VKM Ac-1817D are successfully co-expressed in C.glutamicum ATCC13032. A whole-cell thallus of the engineering bacterium is used as a biocatalyst to transform and produce 9alpha-hydroxyl androstane-4-alkene-3,17-diketone; the mole transformation rate of the substrate androstane-4-alkene-3,17-diketone is up to 99.5 percent. The 9alpha-hydroxyl androstane-4-alkene-3,17-diketone producedby the method disclosed by the invention has the advantages of high efficiency, high specifity, low energy consumption and the like.

The disclosure relates to an AFFT2 cell and a preparation method thereof. According to an embodiment, the cell is transformed with the TCR-T technology. The transformed T cells are blocked in vitro by an antibody drug of suppressive signaling molecules. According to another embodiment, a predicted antigen epitope is centered on a mutant amino acid site, the predicted antigen epitope extends 10 amino acids to each side of the mutant amino acid site, and the predicted antigen epitope serves as a potential antigen epitope. According to a further embodiment, TCR genes in a peripheral blood cell of a patient are knocked out by a CRISPR technology.

The invention relates to the technical field of biology, in particular to a method for synthesizing L-fructose by utilizing whole-cell transformation, a reaction system in the method comprises substrate glycerol, L-glyceraldehyde, pyrophosphoric acid and wet thalli of induced recombinant escherichia coli, and the L-fructose can be obtained after the reaction system is subjected to catalytic reaction. By utilizing the method, the yield of the L-fructose can be improved.