46 results about "Protein labeling" patented technology

The invention belongs to the technical field of gene engineering, and particularly relates to a biotin ligase mutant as well as a coding gene, an expression vector, a recombinant cell and application thereof. The amino acid sequence of the biotin ligase mutant is as shown in SEQ ID NO. 2. The biotin ligase (Bar A) mutant provided by the invention can be efficiently expressed in eukaryotes, the expression level of the biotin ligase (Bar A) mutant is obviously improved in mammalian cells compared with a wild type, and the biotin ligase (Bar A) mutant has good catalytic activity after expression, can effectively catalyze biotinylation of protein containing a biotin receptor sequence, and has good application prospects. The method has a wide application prospect in the fields of biotinylated protein preparation, and protein labeling, positioning, immunodetection, affinity purification, function research and the like based on a biotin-avidin system (BAS).

The disclosed systems and methods involve the semi-quantitative detection of disease-specific protein signatures in biological samples. The system may include a housing with a motor driven substrate holder on rails. The substrate holder is configured to be positioned at multiple locations along the guide rails. Imaging sensors capture images of portions of the substrate at these locations. The system detects markers on the substrate and determines the location of wells based on these markers. Based on the determined location of the wells, color values for each pixel in the wells can be measured. These values may be analyzed to detect disease-specific protein signatures in a variety of sample types.

The invention discloses an application of a biomarker in typing of polymorphic glioblastoma, and the biomarker is combined by selecting at least one of the following categories: at least one of a plurality of gene markers for identifying a proliferative type, a protein marker DLL3 and / or Ki67, a protein marker DL3 and / or Ki67, a protein marker DL3 and / or Ki67, a protein marker DL3 and / or Ki67, a protein marker DL3 and / or Ki67, and a protein marker DL3 and / or Ki67. At least one of a plurality of gene markers for identifying the neurosynaptic type, a protein marker GRMM3 and / or FGFR2; at least one of a plurality of gene markers for identifying the metabolic type, a protein marker P16; and at least one of a plurality of gene markers for identifying the immune regulation type, and at least one of protein markers CD44, C1R and Ki67. The application provides comprehensive features of EAS-GBM, and enhances understanding of occurrence, clinical stratification and treatment strategies of different ancestral tumors.

The present application relates to the technical field of fluorescent dyes, in particular to an asymmetric pentamethine cyanine compound. The compound comprises a structure as shown in formula I. The compound provided by the present application has good water solubility, near-infrared absorption, high fluorescence quantum yield and good molar absorption coefficient, and can be used in nucleic acid labeling, DNA sequencing, cell imaging, protein labeling or specific recognition of amino acids.

This invention provides a method and apparatus for splitting single-cell mixed sample sequencing data, relating to the field of biotechnology. The splitting method includes: capturing and sequencing single-cell suspensions using a single-cell platform; then performing reference genome alignment, cell identification, and gene expression level quantification on the sequencing data using Cellranger; splitting the cell data identified in step a into two groups of cell data for different sexes based on SNP locus information from the 1000 Genomes Project; and distinguishing the two groups of cell data from male or female samples based on the proportion of sex-specific genes expressed in the two groups of cell data. This splitting method eliminates the need for additional experimental operations such as protein labeling and genome sequencing, and can provide accurate and reliable data splitting even when individual SNP information is unavailable.

The invention relates to a nitroimidazole group meso-substituted heptamethine cyanine dye as well as a preparation method and application thereof. According to the dye, a nitroimidazole group is introduced into the middle position of a heptamethine cyanine parent nucleus, so that the dye has excellent absorption characteristics in a near-infrared region, the excitation wavelength is 730-780 nm, the emission wavelength is 800-860 nm, and the dye has good tissue penetrating power. The nitroimidazole group can effectively quench fluorescence in an excited state through a light-induced electron transfer effect, energy is promoted to be released in a non-radiative transition mode, the photothermal conversion efficiency is remarkably improved, and meanwhile high light stability and low fluorescence quantum yield are kept. The dye can be further prepared into a nano preparation and shows excellent biocompatibility and tumor targeting ability. The compound has wide application prospects in the fields of non-diagnostic or therapeutic protein labeling, bioimaging, photothermal therapy and the like, is especially suitable for preparing efficient photosensitive reagent drugs for tumor photothermal therapy, and provides a new strategy for design of near-infrared photothermal diagnosis and treatment materials.

Provided are diagnostic and treatment methods,based on plasma protein markers for neurodegenerative diseases such as mild cognitive impairment (MCI) and Alzheimer's Disease (AD),as well as kits for diagnosing and / or treating these condition.Machine learning systems and methods for assessing the risk for a subject having a neurodegenerative disease based on measured protein marker levels are also provided.

The invention discloses an ultra-stable red fluorescent protein. The fluorescent protein disclosed by the invention is a protein with an amino acid sequence SEQ ID No.4. Experiments prove that the fluorescent protein has excellent electron microscope sample preparation resistance, can retain more fluorescent signals after osmic acid treatment, and can tolerate embedding of Epon resin; meanwhile, the fluorescent protein has excellent thermal stability, and can retain more fluorescent signals at 90 DEG C; in addition, the fluorescent protein has high chemical stability and light stability. Based on the related properties of the fluorescent protein, the fluorescent protein can be used in the fields of protein labeling, various types of fluorescence imaging and super-resolution photoelectric correlated imaging, and is used for tracking the structural and morphological changes of samples such as proteins, subcellular organelles, local cell regions and cells; the kit can be used for packaging related viruses or transgenic animals, marking specific proteins, specific organelles or specific cells, and realizing rapid transparent tissue imaging and expansion super-resolution imaging.

The invention belongs to the technical field of biological medicines, and particularly relates to sulfonium salt polypeptide or protein as well as a preparation method and application thereof. Polypeptide or protein containing cysteine and a sulfonium salt compound are used as raw materials, and the sulfonium salt compound is used for alkylation of cysteine at a specific site of the polypeptide or protein to prepare the sulfonium salt polypeptide or protein. The sulfonium salt polypeptide or protein is used as a probe for covalently labeling tryptophan in a lysine methylation reader protein recognition pocket. According to the method disclosed by the invention, different types of sulfonium salt polypeptides and protein probes can be simply, conveniently and efficiently prepared, and the designed annular sulfonium salt with a novel skeleton has an obvious improvement on the polypeptide or protein labeling yield of reader protein. The prepared sulfonium salt probe not only can be used for identifying lysine methylation modified reader protein and finding a therapeutic target for disease-related pathways, but also can be used for modifying tryptophan at a specific site of an antibody-coupled drug and provides a powerful tool for targeted therapy research of tumors.

The invention discloses a space-time marking method for a living cell endoplasmic reticulum proteome, and belongs to the field of proteomics. The technical problem to be solved by the invention is how to mark endoplasmic reticulum proteins. The space-time labeling method for the living cell endoplasmic reticulum proteome comprises the following steps: treating a cell to be detected by using a metal iridium complex Ir3 and a thiomethylene quinone precursor probe to obtain the cell treated by the Ir3 and the probe; the thiomethylene quinone precursor probe is a compound or a derivative thereof obtained by connecting biotin and a thiomethylene quinone precursor with a linking group; and irradiating the Ir3 and the cells treated by the probe with blue light to realize space-time labeling of the endoplasmic reticulum proteome of the living cells. The method disclosed by the invention can be used for performing space-time labeling on the endoplasmic reticulum proteome of the living cell, has the characteristics of high specificity and in-situ protein labeling, and has nanoscale space-time resolution.

The present invention discloses an anti-pigeon adenovirus Hexon protein monoclonal antibody, the anti-pigeon adenovirus Hexon protein monoclonal antibody is monoclonal antibody 1H5-8-14-5, wherein the amino acid sequences of the heavy chain variable region and the light chain variable region of monoclonal antibody 1H5-8-14-5 are shown in SEQ ID NO.3 and SEQ ID NO.4, respectively. The present invention also discloses a double antibody sandwich ELISA diagnostic kit for detecting pigeon adenovirus antigens, the kit comprising an enzyme labeling plate coated with an anti-Hexon protein polyclonal antibody, Hexon protein, HRP-labeled anti-pigeon adenovirus Hexon protein monoclonal antibody, a negative control, a color developing solution, a washing solution, and a stop solution. The kit of the present invention can effectively detect pigeon adenovirus, provides a new technical means for pigeon adenovirus prevention and control, and the detection result is accurate and specific, with good application value.

A protein marker panel for screening clinical futile recanalization (FR) in patients with large vessel occlusion-induced acute ischemic stroke (LVO-AIS) and use thereof are provided. The protein marker panel includes GUCA2A, CCL14, STAB1, and VSIG4. A combined diagnostic value of the protein marker panel is high, and receiver operating characteristic (ROC) curve analysis demonstrates an efficacy in distinguishing and screening FR patients, with an area under the curve (AUC) of 0.959, indicating desirable sensitivity and specificity. Such a protein marker panel shows promise as a significant indicator for clinical decision-making in FR evaluation.

The application discloses a fluorescent probe for adjacent thiol protein labeling and bio-imaging and application thereof, which is used for in-vitro labeling of adjacent thiol proteins and bio-imaging of endogenous adjacent thiol in living cells. Based on the active dimethyl sulfide site on cyclopentanone, a series of adjacent thiol protein recognition probes (IDAs) with high specificity, high stability and biocompatibility are constructed and screened, so that in-vitro fluorescent detection of adjacent thiol proteins and in-situ fluorescent labeling of adjacent thiol proteins in cells are realized.

The present invention relates to an integrated centrifugal device and method for analyte processing, particularly for the separation, enrichment, labeling, and analysis of nanovesicles such as extracellular vesicles (EVs). The device leverages a compact, rotatable substrate to execute multi-step assay protocols that may include chromatographic separation, centripetal fluid transport, immuno-capture, and protein labeling, all under low-speed centrifugal conditions. The device architecture enables automated, hands-free operation without requiring ultracentrifugation or specialized personnel. Fluidic modules including sedimentation, chromatography, displacement, and multiple assay chambers may be functionally integrated through a series of valves, channels, and immiscible liquid-based displacement mechanisms, facilitating precise sample handling, minimal loss, and multiplexed analysis.

The application relates to the field of chemiluminescence immunoassay, in particular to a water-soluble acridine sulfonamide carboxylic acid label, a preparation method, application and kit, wherein in some embodiments, the water-soluble acridine sulfonamide carboxylic acid label is coupled by one-step reaction of acridine sulfonamide and a water-soluble glycine tripeptide, and the synthesis is simple and the yield is high. The water-soluble acridine sulfonamide carboxylic acid label not only increases water solubility, but also prolongs a connecting arm, and solves the water solubility problem of a protein label.

The application discloses a method for preparing aromatic benzyl propargyl ketone by light induction and biological application, belongs to the technical field of organic synthesis and biological medicine, and converts aromatic benzyl propargyl alcohol into aromatic benzyl propargyl ketone under the condition of light induction; the change of the functional group before and after light induction is that the hydroxyl alkyne without reaction activity is converted into the carbonyl alkyne with click reaction activity, fluorescence enhancement can be realized, and the method can be used for imaging and tracing; and the aromatic benzyl propargyl ketone can react with a compound containing an amino group or a biological macromolecule to realize the killing of tumor cells. The method uses light as a starting switch, the reaction condition is simple, controllability is good, no additional catalyst is needed, and the method is easy to mass-produce, so the method has wide application prospects in polypeptide or protein labeling, anti-tumor and the like.

The present invention relates to the field of protein labeling or tracing, and particularly to a composition and method for labeling or tracing a target protein. The method first analyzes the structure of the target protein and identifies a loop sequence on the protein surface that faces outward. Then, through molecular cloning methods, a small tag (such as an HA tag) with flexible amino acid linker peptides at both ends is inserted into the middle of the loop sequence. Finally, a nanobody fused to the small tag and fused to a fluorescent protein is expressed. This method utilizes the nanobody's ability to specifically recognize the target protein surface tag to achieve intracellular tracing of the target protein.

Provided are a fluorescent probe, a preparation method therefor and a use thereof. The fluorescent probe sensitively and specifically responds to viscosity, and can be used for the specific fluorescence labeling of proteins as well as in the quantification, detection or kinetic study of proteins and the imaging of cells, tissues and living bodies.

The invention provides a vitamin B12 detection kit, belongs to the technical field of in-vitro diagnostic reagents, and particularly provides a vitamin B12 detection kit, which comprises: a labeling reagent, which comprises a vitamin B12 derivative labeled by a chemiluminescent marker; the alkaline dissociation agent comprises an alkaline solution, sodium chloride and urea; the acidic dissociation agent comprises an acidic solution, ethylenediamine tetraacetic acid, an organic solution and a reducing agent; and the solid-phase reagent comprises protein-labeled magnetic particles for specifically recognizing the vitamin B12. The vitamin B12 detection kit provided by the invention has relatively low detection limit and relatively high stability and accuracy, does not contain toxic reagents, and is suitable for clinical large-scale popularization and application.

The application discloses an enamine N-oxide containing a naphthalimide fluorescent group, a preparation method of the enamine N-oxide and application of the enamine N-oxide in a fluorescent probe. 2+ The application also provides a general synthesis method of the compound, wherein an amino functional group containing structural fragment is reacted with 4-bromo-1,8-naphthalic anhydride, and then the enamine N-oxide is generated through steps of hydroxyl substitution, bromine substitution and alkyne addition. 2+ When the compound is applied as the fluorescent probe, the compound has high sensitivity, excellent space-time resolution and light stability, is suitable for dynamically monitoring changes of Fe 2+ content in the iron death process and related protein marker research, and provides a new generation of molecular tools for iron death mechanism research, and has important application prospects in the fields of disease model construction and drug screening.

The present application relates to the field of biomedical technology, and in particular to an application of a protein marker composition in radiation pneumonitis; the application includes using a protein marker composition above an expression level as a biomarker for radiation pneumonitis, the protein marker composition including angiopoietin-like protein 4, growth differentiation factor 15, chemokine CXC ligand, and chemokine 20; by performing cytokine chip detection and screening on peripheral blood specimens of multiple lung cancer patients undergoing chest radiotherapy before radiotherapy, it was found that high expression of angiopoietin-like protein 4, growth differentiation factor 15, chemokine CXC ligand 10, chemokine CXC ligand 13, chemokine CXC ligand 14, and chemokine 20 is a risk factor for radiation pneumonitis, and combining these cytokines can improve the prediction accuracy of radiation pneumonitis. Therefore, the above-mentioned cytokine combination may become a powerful early prediction tool for radiation pneumonitis in clinical practice.

The invention discloses a Sortase A transpeptidase mutant and application thereof in the technical field of bioengineering, the Sortase A transpeptidase mutant is obtained through single mutation or double mutation on the basis of a protein sequence shown in SEQ ID NO.2, the protein sequence shown in SEQ ID NO.2 is a truncated mutant at the 60th-206th site made on wild type Sortase A transpeptidase shown in SEQ ID NO.1, and the Sortase A transpeptidase mutant is obtained through single mutation or double mutation on the basis of the protein sequence shown in SEQ ID NO.2. The Sortase A transpeptidase mutant provided by the invention has higher yield, activity and thermal stability, and has wider application conditions. Besides, a cysteine is introduced to the C terminal of the Sortase A transpeptidase mutant protein, and the Sortase A transpeptidase mutant is fixed on the magnetic beads by utilizing the principle of sulfydryl covalent coupling, so that the application value of the Sortase A transpeptidase mutant in protein labeling is realized.

The invention relates to a method for the profiling of membrane and cargo proteins from extracellular vesicles (in combination or without simultaneous isolation of extracellular vesicles from cell cultures and body fluids) consisting of a 3D ELISA technique, where the 3D support is beads placed in the wells of a microplate or in microtubes ("in the volume" reaction model) or on the surface of a filter membrane ("filtration" reaction model) and putted in contact with the extracellular vesicles.

The application discloses a transcription factor identification method based on a Transformer-Encoder and a multi-scale convolutional neural network. The method first extracts global features of a protein sequence using the Transformer-Encoder, then further extracts multi-scale local features from the global features using the multi-scale convolutional neural network, and finally fuses the extracted multiple features to output a probability of the protein sequence being a transcription factor. The transcription factor identification method based on the Transformer-Encoder and the multi-scale convolutional neural network can accurately identify whether an unknown protein sequence is a transcription factor, can quickly determine the transcription factor only by relying on the protein sequence, and greatly improves the protein labeling efficiency.

The present application belongs to the technical field of fluorescent probe, and particularly relates to a new method for constructing a meso-aryl-substituted heptamethine cyanine dye. The present application uses cyanine ketone as a raw material, aryl lithium as a reaction reagent, and a meso-aryl-substituted heptamethine cyanine (ArCy7) dye is obtained through a one-pot reaction with a high yield. The ArCy7 dye prepared by the method of the present application effectively improves the water solubility, chemical / photo stability and anti-aggregation ability of the Cy7 dye, thereby promoting the application of the dye in constructing a fluorescent probe, protein labeling or tumor diagnosis and treatment.

The invention discloses an adjacent protein marking method and application. The invention provides an adjacent protein labeling method, which comprises the following steps: by taking an aldehyde / keto-phenol small-molecule probe as a substrate, catalyzing the substrate into a substrate containing active free radicals by using a catalyst, and forming a covalent label by the substrate containing the active free radicals and a target protein to obtain a labeled protein. According to the method, the aldehyde / keto-phenol probe with high reaction activity is combined with a hydrazide / hydroxylamine reversible enrichment process, so that marker site identification with high sensitivity and high coverage is realized, and the limitations of site level analysis, cell physiological disturbance and the like of a traditional proximity labeling method are overcome. The method is simple to operate, good in reproducibility, high in data result reliability and accuracy and more real and reliable in identification result. By means of efficient site level analysis, the proteome can be identified and marked more accurately, and more sensitive protein structure analysis is realized.

The present invention relates to the technical fields of fluorescent dye synthesis, fluorescence imaging, and bio-sensing. Disclosed are an amide cyanine dye, an efficient synthesis method therefor, and a use thereof in fluorescence imaging. Compared with traditional cyanine dye synthesis methods, the amide cyanine dye synthesis method of the present invention is simple and has few by-products, short reaction time, high yield, a stable structure, and high universal applicability. By increasing the length of a conjugated chain, the absorption and emission wavelengths of the amide cyanine dye can be expanded from a short-wave near-infrared region to a near-infrared-II band. Experiments have proven that the amide cyanine dye has good photophysical properties and the potential for biofluorescence imaging, and can be used in biometric imaging, super-resolution fluorescence imaging of cellular mitochondria, protein labeling, specific recognition of antibodies, nucleic acid labeling, DNA sequencing, tumor photodynamic therapy, etc. On the basis of the advantages, the amide cyanine dye of the present invention has good prospects for application in the field of biofluorescence imaging research.

The invention relates to a caenorhabditis elegans model-based anti-aging effect evaluation method and application, and belongs to the technical field of anti-aging effect evaluation. The invention relates to a caenorhabditis elegans model-based anti-aging efficacy evaluation method, which comprises: S1, culturing a synchronized caenorhabditis elegans model on a nematode growth solid culture medium comprising a sample to be detected and E.coli OP50 escherichia coli for 3-9 days, and taking the cultured caenorhabditis elegans model as a sample group; culturing the synchronized caenorhabditis elegans model on a nematode growth solid culture medium containing E.coli OP50 escherichia coli for 3-9 days to obtain a blank group; s2, a plurality of caenorhabditis elegans models are selected from the sample group and the blank group for environment stress treatment; s3, performing fluorescence detection on the caenorhabditis elegans model subjected to environmental stress treatment, comparing the fluorescence intensity of a sample group with the fluorescence intensity of a blank group, and evaluating the anti-aging effect of the to-be-detected sample; wherein the caenorhabditis elegans model is a caenorhabditis elegans model of which SIR-2.1 protein is marked with fluorescent protein. And the anti-aging effect can be evaluated more accurately and efficiently.

The application belongs to the technical field of biological detection, and particularly relates to a probe compound for CoA detection, a fluorescent probe and application, comprising a modified rhodamine series fluorescent dye, a pantothenate kinase inhibitor, a HaloTag, a Nanoluc luciferase and a pantothenate kinase fusion protein; through protein labeling, a series of biosensors are obtained, coenzyme A concentration in living cells can be rapidly detected, and rapid screening of coenzyme A drugs is regulated; through rational design and modification of the chemical probe molecules, and engineering modification of the sensor proteins, the chemical probes can label the sensor proteins in living cells, and then the bioluminescent sensors working in living cells are obtained, the requirements of rapid and high-sensitivity detection of CoA can be met, and the drugs capable of regulating the change of coenzyme A concentration can be high-throughput screened.

Disclosed in the present invention is an ultra-stable red fluorescent protein. The fluorescent protein disclosed in the present invention is a protein having an amino acid sequence of SEQ ID NO: 4. Experiments have demonstrated that the fluorescent protein has great tolerance to electron microscopy sample preparation, can retain more fluorescence signals after an osmium tetroxide treatment and can tolerate embedding in an Epon resin. Moreover, the fluorescent protein has great thermal stability and can retain more fluorescence signals even at 90°C. In addition, the fluorescent protein has relatively high chemical stability and light stability. On the basis of related properties of the fluorescent protein, the protein can be used in the fields of protein labeling, various types of fluorescence imaging, and super-resolution correlative light and electron microscopy, and used for tracking changes in structures and morphologies of samples such as proteins, subcellular organelles, local regions of a cell, and entire cells. The fluorescent protein can be used for packaging related viruses or generate transgenic animals, and for labeling specific proteins, specific organelles or specific cells, thereby achieving rapid tissue clearing imaging and expansion super-resolution microscopy.