18 results about "Protein Cleavage" patented technology

The invention relates to the technical field of biological detection, and particularly discloses a one-tube method detection system based on Cas protein modification and application of the one-tube method detection system. An epitope is inserted into the Cas protein, so that the cis-cleavage activity of the Cas protein is weakened. Starting from the Cas protein, the Cas is modified through a protein engineering strategy, the problem of competition between RPA amplification and Cas protein cleavage is successfully solved, and the one-tube method detection system based on Cas protein modification has the characteristics of quick response, high sensitivity, high reliability and simplicity and convenience in operation; and the kit has important practical significance on detection, prevention and treatment of early infection.

The present invention provides mRNA sequences comprising at least one coding region, encoding for at least one epitope of a protein, or of a fragment, variant or derivative thereof, of a virus of the genus rotavirus. Particularly preferred is the protein respectively the protein cleavage product VP8* of rotavirus. The mRNA sequence may be used as a vaccine or generally as a pharmaceutical composition for prophylaxis or treatment of rotavirus infections.

The application discloses a protein cleavage site identification method and system based on mass spectrum data and a storage medium. The original mass spectrum data is preprocessed to obtain mass spectrum-derived peptides corresponding to an input precursor protein sequence; the mass spectrum-derived peptides are compared to the corresponding precursor protein sequence to construct a protein site coverage matrix; based on the protein site coverage matrix, potential cleavage regions and potential cleavage sites in the protein are identified; statistical significance analysis is performed on the potential cleavage sites in the protein to extract cleavage site neighborhood sequences; and the statistical significance of the potential cleavage sites in the protein is used to filter the potential cleavage sites to obtain high-confidence protein cleavage sites. The application has low dependence on known protease cleavage rules, can identify cleavage events mediated by unknown or non-classical cleavage modes, and expands the application range of protein cleavage site identification.

There is a modified coronavirus spike antigen protein and uses therefor. The spike antigen protein of coronavirus exhibits suppression of cell membrane fusion ability and improves safety by modifying two protein cleavage sites present in the coronavirus spike protein. In addition, inoculation with a vaccine having the antigen protein induces production of a large number of neutralizing antibodies to inhibit invasion of coronavirus into cells, thereby suppressing viral proliferation.

The application discloses a protease catalytic type attribution method based on protein cleavage site embedded vectors, comprising the following steps: constructing a cleavage site reference set of known protease substrates; obtaining N reference site vectors and M attribution site vectors; performing standardization processing on the N reference site vectors and the M attribution site vectors; calculating M*K first similarities and M*N second similarities; obtaining the nearest neighbor reference sites corresponding to each attribution site; obtaining the nearest neighbor support labels and the nearest neighbor support degrees of each attribution site; obtaining a credibility threshold required for attribution of the catalytic type of the attribution site; comparing the first similarity, the similarity difference and the nearest neighbor support degree with the credibility threshold required for attribution of the catalytic type of the attribution site; generating a corresponding credibility level or marking the attribution site as an uncertain candidate site; and the application can output attribution results of each attribution site according to the same data structure.

The present invention provides mRNA sequences comprising at least one coding region, encoding for at least one epitope of a protein, or of a fragment, variant or derivative thereof, of a virus of the genus rotavirus. Particularly preferred is the protein respectively the protein cleavage product VP8* of rotavirus. The mRNA sequence may be used as a vaccine or generally as a pharmaceutical composition for prophylaxis or treatment of rotavirus infections.

The invention provides a polynucleotide detection method, a kit and application, and relates to the technical field of biology. The polynucleotide detection method comprises the following steps: at least one group of primer pairs is provided, and a primer at one end of each primer pair contains a first quenching group, an exonuclease recognition site and a luminous group; the primer at the other end contains a second quenching group; amplifying a sample to be detected by using the primer pair to obtain an amplification product, and cutting the amplification product by using exonuclease and Cas protein which is guided by gRNA and has a targeted cutting function. According to the detection method, the problem that multiple detection cannot be efficiently realized on the basis of Cas protein detection polynucleotide in the prior art is solved.

The invention discloses an electrochemical sensor based on TdT enzyme and CbAgo synergistic mediation and application of the electrochemical sensor in cobra venom protein detection, and belongs to the technical field of electrochemical biosensors. Through magnetic bead enrichment, CbAgo protein cleavage and TdT extension reaction, and construction of a TdT enzyme and CbAgo protein synergistically mediated protein-nucleic acid conversion technology, a detection target is converted from cobra venom protein into a nucleic acid product, then the nucleic acid product is utilized to activate a Cas12a system to cut a probe P combined with a gold electrode, finally, the probe P is converted into an electrochemical signal, and the electrochemical signal is detected. The efficient and accurate detection of the cobra venom protein is realized. The electrochemical biosensor disclosed by the invention is high in sensitivity and good in specificity, and has extremely high application value in the aspects of accurate identification and quantitative analysis of cobra venom protein.

A method for detecting cleavage of a target protein or protein of interest (POI) in a non-purified sample, wherein the target protein comprises a first signature peptide or domain and a second signatu

The application discloses an electrochemical sensor based on TdT enzyme and CbAgo synergistically mediated and application thereof in detection of cobra venom protein, and belongs to the technical field of electrochemical biosensors.The application constructs a protein-nucleic acid conversion technology mediated by TdT enzyme and CbAgo protein through magnetic bead enrichment, CbAgo protein cleavage and TdT extension reaction, converts the detection target from cobra venom protein into a nucleic acid product, and then utilizes the nucleic acid product to activate a Cas12a system to cleave a probe P combined on a gold electrode, and finally converts into an electrochemical signal, so that efficient and accurate detection of the cobra venom protein is realized.The electrochemical biosensor has high sensitivity and good specificity, and has extremely high application value in accurate identification and quantitative analysis of the cobra venom protein.

The invention discloses an anti-aging polypeptide detection method and system based on Label-free. The method comprises the following steps: extracting protein in a sample for pretreatment; the method comprises the following steps: carrying out enzymolysis on a polypeptide sample stored in an acetic acid aqueous solution, and cutting protein into peptide fragments by using trypsin; carrying out mass spectrometry detection and analysis by using an improved Label-free technology; and performing layered search on the mass spectrum parameters by using an Ivy optimization algorithm to obtain a detection result of the anti-aging polypeptide. According to the invention, the accuracy and sensitivity of detection are improved, the cost is reduced, the interference of a marking agent is avoided, and a scientific basis is provided for research and development of anti-aging drugs and identification of biomarkers.

An inhibitor of the interaction between CD97 and GSDME having antitumor activity, and its use. [Solution] A compound represented by formula (I), its pharmaceutically acceptable salt, solvate, or deuteride is provided. JPEG2026069453000042.jpg3673 The compound of the present invention inhibits the interaction process between GSDME and CD97 in tumor cells, thereby improving the sensitivity of NK cells to killing tumor cells and inducing an immunoantitumor effect. Furthermore, the compound improves the sensitivity of tumor cells to pyrotosis by blocking the protective effect of CD97 against GSDME protein cleavage within tumor cells. Therefore, the compound can be used in the treatment of GSDME and CD97-double-positive malignant tumors, as well as in combination with chemotherapy and immunotherapy, improving the sensitivity of malignant tumors to chemotherapy and immunotherapy, and further extending the overall survival of malignant tumor patients.

The application relates to the technical field of biological detection, and specifically discloses a one-tube detection system based on Cas protein modification and application thereof. An antigen epitope is inserted into the Cas protein, so that the cis cleavage activity of the Cas protein is weakened. Starting from the Cas protein, the Cas is modified through a protein engineering strategy, the competitive problem between RPA amplification and Cas protein cleavage is successfully overcome, and the one-tube detection system based on the above Cas protein modification has the characteristics of rapid response, high sensitivity, high reliability and simple operation, and has important practical significance for early infection detection, prevention and treatment.

One aspect relates to a modified coronavirus spike antigen protein and uses thereof. It was confirmed that a spike antigen protein of coronavirus, according to one aspect, exhibited suppression of cell membrane fusion ability and improvement in safety by modifying two protein cleavage sites present in a coronavirus spike protein of the coronavirus. In addition, inoculation with a vaccine using said antigen protein induces the production of a large amount of neutralizing antibodies to inhibit the invasion of the coronavirus into cells, thereby suppressing viral proliferation. Accordingly, the present invention can be used in various industries and markets, such as prevention of coronavirus infection, alleviation and treatment of symptoms, infection diagnosis, etc.

This invention discloses a dual-luciferase reporter cell line for detecting CRISPR-Cas protein cleavage activity and its applications. The reporter cell line of this invention expresses the nanoluciferase gene Nluc with the housekeeping gene ACTG1, avoiding the influence of intracellular environmental changes on the activity of the nanoluciferase Nluc. Changes in Nluc activity reflect the cleavage activity of the CRISPR-Cas protein, overcoming the shortcomings of existing GFPs, which have a long half-life and cannot quickly respond to double-strand breaks at gene sites. Furthermore, the reporter cell line of this invention can also be used to screen CRISPR-Cas protein inhibitors. This invention has used the constructed reporter cell line to screen small molecule compounds that can inhibit SpCas9 cleavage activity intracellularly. The screening process is simple, convenient, and provides stable signals.

The present invention concerns a method for detecting cleavage of a protein of interest in a non-purified test sample, wherein said protein of interest comprises at least a first signature peptide present in a first domain and at least a second signature peptide present in a second domain, wherein the method comprises the steps of: heating the non-purified test sample to provide a heated test sample; separating soluble from insoluble protein in the heated test sample to produce soluble and insoluble protein fractions of said heated test sample; and determining, in the soluble and / or the insoluble protein fraction of step b), a first relative level, which is the level of the first signature peptide as compared to a control level, and a second relative level, which is the level of the second signature peptide as compared to a control level, wherein cleavage is detected by a difference between said first and second relative levels in the soluble protein fraction and / or by a difference between said first and second relative levels in the insoluble protein fraction.

This invention develops a nanoprotease based on a bimetallic two-dimensional organic nanoframework and explores its catalytic mechanism. This two-dimensional structure achieves a 3-5 fold increase in hydrolysis efficiency by maximizing the accessibility of active sites and reducing mass transfer resistance, significantly outperforming existing reports. Metal doping and organic ligand properties further enhance Lewis acidity, thereby optimizing peptide bond hydrolysis performance. The organic ligand induces protein unfolding through a hydrophobic interface, exposing protein cleavage sites and accelerating the enzymatic reaction rate. CeCuBDC exhibits excellent stability and superior reusability during protein hydrolysis. Furthermore, this material can hydrolyze various proteins and mixed protein samples, and demonstrates outstanding catalytic activity in selectively cleaving peptide bonds containing hydrophobic residues. As a two-dimensional bimetallic MOF nanoprotease, CeCuBDC shows broad prospects for proteomics applications.

The application relates to the technical field of nucleic acid detection, and discloses a construction method and application of an RPA-Cas12a light control one-tube method reaction system. The construction method is as follows: an RPA primer pair and a crRNA sequence are designed; an RPA system is configured; Block split crR-C and pc-DNA are prepared; a Cas12a in-vitro trans-cleavage system is configured; and the RPA-Cas12a light control one-tube method reaction system is constructed. Through a time sequence separation strategy, the problem that amplification reaction and Cas protein cleavage are incompatible in the same tube is solved; after constant-temperature amplification is completed, the prepared pc-DNA is photoactivated to form a straight chain, a subsequent strand displacement reaction occurs, and then the Cas12a protein cleavage function is activated to generate a fluorescence signal; the detection method is rapid and highly accurate, and can be used for rapid detection of drug addiction markers.