40results about How to "Maintain native conformation" patented technology

The invention provides an aptamer EpCAM (epithelial cell adhesion molecule) Ccut of an EpCAM as well as a preparation method and application thereof, relating to nucleic acids. The aptamer has high specificity and affinity. The aptamer has a G tetramer structure or a stem-loop structure. The preparation method comprises the steps of designing and synthesizing a single-stranded DNA (deoxyribonucleic acid) random oligonucleotide bank, screening a target oligonucleotide sequence, and identifying the target protein binding specificity and affinity of the target oligonucleotide sequence by a flow analysis method. The screened aptamer does not have toxicity, has small molecular weight and good permeability, is easy to synthesize and label, only specifically identifies EpCAM proteins and cell lines expressing the EpCAM proteins, and does not have a function of identifying the cell lines which do not express the proteins.

The invention provides an aptamer EpCAM (epithelial cell adhesion molecule) B of an EpCAM as well as a preparation method and application thereof, relating to nucleic acids. The aptamer has high specificity and affinity. The aptamer has a G tetramer structure or a stem-loop structure. The preparation method comprises the steps of designing and synthesizing a single-stranded DNA (deoxyribonucleic acid) random oligonucleotide bank, screening a target oligonucleotide sequence, and identifying the target protein binding specificity and affinity of the target oligonucleotide sequence by a flow analysis method. The screened aptamer does not have toxicity, has small molecular weight and good permeability, is easy to synthesize and label, only specifically identifies EpCAM proteins and cell lines expressing the EpCAM proteins, and does not have a function of identifying the cell lines which do not express the proteins.

The present invention relates to a glycoside hydrolase family 7 protein gene, the nucleotide sequence of the glycoside hydrolase family 7 protein gene is shown in SEQ ID No.1. It also relates to the protein encoded by the gene, the amino acid sequence of which is shown in SEQ ID NO.2. The present invention designs a new gene sequence capable of expressing the glycoside hydrolase family 7 protein, and further utilizes the pET28 vector to construct a recombinant plasmid and transform it into an E. coli expression strain to realize the soluble expression of the expression product and obtain a large amount of soluble form of Recombinant glycoside hydrolase family 7 protein; in the expression system of the present invention, the recombinant glycoside hydrolase family 7 protein can be folded in an appropriate manner and maintain the natural conformation, and the prepared protein has the ability to hydrolyze sodium carboxymethyl cellulose to produce glucose It has good enzyme activity, and has good enzyme activity under the condition of pH3.5‑5.0, and has a certain activation effect in the presence of copper ions.

The invention provides an aptamer EpCAM (epithelial cell adhesion molecule) D of an EpCAM as well as a preparation method and application thereof, relating to nucleic acids. The aptamer has high specificity and affinity. The aptamer has a G tetramer structure or a stem-loop structure. The preparation method comprises the steps of designing and synthesizing a single-stranded DNA (deoxyribonucleic acid) random oligonucleotide bank, screening a target oligonucleotide sequence, and identifying the target protein binding specificity and affinity of the target oligonucleotide sequence by a flow analysis method. The screened aptamer does not have toxicity, has small molecular weight and good permeability, is easy to synthesize and label, only specifically identifies EpCAM proteins and cell lines expressing the EpCAM proteins, and does not have a function of identifying the cell lines which do not express the proteins.

The invention relates to a production method of toxin Tx4 (6-1) label-free recombinant protein. Gene provided by the invention is DNA molecule shown by a sequence 1 in a sequence table. The production method includes that (1), soluble high-level fusion expression of the toxin gene in Escherichia coli can be realized by utilizing a gene sequence of the sequence table 1; (2), recombinant protein completely identical with naturally mature Tx4 (6-1) protein in amino acid sequence is obtained by cutting and removing non-target protein from soluble protein in fusion expression; (3), the obtained recombinant protein has high bioactivity. By the production method, DNA sequence of Tx4 (6-1) is optimized, and expression strain and expression vector are screened; a method for efficiently producing active Tx4 (6-1) recombinant protein is provided, thereby being conducive to conducting detained research on insect-resistant characteristic and bio-safety of the toxin protein and of important significance in screening corresponding insect-resistant plants and high-toxicity transgenic biological insecticides.

The present invention relates to a new pectinase gene, which is shown in the nucleotide sequence of SEQ ID NO.1 in the sequence table; or has more than 90% of the nucleotide sequence shown in SEQ ID NO.1 A sequence that is homologous and encodes the same biological function protein; or a sequence that can hybridize with the nucleotide sequence shown in SEQ ID NO.1 and encodes the same biological function protein. The nucleotide sequence of SEQ ID NO.1 in the present invention can use the pET32 vector and Escherichia coli expression strain to realize the fusion of the expression product and the solubilizing factor Trx, and obtain a large amount of Trx pectinase fusion protein in soluble form , and purified by nickel affinity chromatography and DEAE anion exchange method to obtain high-purity and high-activity recombinant pectinase protein, which provides the basis for mass production of recombinant pectinase.

The invention discloses an application of chlorate in preparation of a biochemical reagent for eliminating a negative value or a zero value in a determination result. According to a novel use of the chlorate, the chlorate capable of providing a proper preservation and reaction environment to a to-be-determined object is added in the biochemical reagent, so that the to-be-determined object presents deserved biological activities, and the native conformation of the to-be-determined object is maintained; and the constitution of the to-be-determined object or a tool enzyme active center is participated, the normal operation of a reaction is guaranteed, a real detection result is obtained, and a phenomenon of the negative value or the zero value in the sample detection result is eliminated.

The invention belongs to the technical field of molecular biology, and in particular relates to a human platelet antigen genotyping liquid phase chip and a detection method thereof. Human platelet antigen genotyping technology is an important technical means to provide patients with matching platelets and promote the safety and effectiveness of clinical platelet transfusion. However, the existing human platelet antigen genotyping technology has low throughput and high accuracy. Indexes such as sensitivity and sensitivity need to be improved. The liquid phase chip of the present invention includes primers 1-24, connection probes 25-46 and fluorescently encoded microspheres coated with detection probes 47-68, and the human platelet antigen gene is completed through amplification, connection and hybridization reactions. Typing detection. The liquid phase chip and detection method adopted in the present invention have the advantages of large flux, high sensitivity, strong specificity, good repeatability, wide linear range, simple operation, strong flexibility, and wide application range, and are clinically accurate, Efficient and practical human platelet antigen genotyping detection method.