43 results about "Polyhistidine-tag" patented technology

The present invention relates to a recombinant human elastin protein, and its preparation method and application. The recombinant human elastin protein comprises one or more elastin domains in the amino acid sequence of the full-length human elastin protein as shown in SEQ ID NO.1, as well as one or more of a secretion tag, a histidine tag, a fluorescent protein, and a protease cleavage site. The amino acid sequence of the recombinant human elastin protein is shown in SEQ ID NO.2. The nucleotide sequence is a recombinant plasmid, a recombinant vector, or a recombinant bacterium. The preparation method comprises: synthesizing the nucleotide sequence as shown in SEQ ID NO.1, constructing a recombinant protein, inducing expression, centrifuging, purifying, and drying to obtain the recombinant human elastin protein as shown in SEQ ID NO.2. The application is to detect and evaluate the anti-aging, anti-wrinkle, and firming effects of the recombinant human elastin protein, as well as in cosmetics. The preparation method of the present invention is simple, the protein expression level is high, and the cosmetic product has anti-aging, anti-wrinkle, and firming effects.

Either wild type or mutant Serratia marcescens Nuclease (“SMN”) is engineered to display a C-terminal Chitin Binding Domain (CBD-tag), followed, at the C-terminus side of the CBD-tag, by a poly-histidine tag (His-tag), where the His-tag is preferably a 6-mer and preferably is preceded by a Gly-Ser linker, thereby generating a recombinant SMN protein that retains dual affinity tags (a CBD-tag and a His-tag) at the C-terminus, to make it easily removed from a reaction solution following digestion of nucleic acids in the reaction mixture. It can also be used for binding SMN to a solid support for use in nucleic acid digestion in a sample contacted with the solid support.

The invention discloses an in-vitro expression and purification preparation method of Salsolinol synthetase, and belongs to the field of gene engineering and protein expression. The method comprises the following steps: firstly, constructing a Salsolinol synthetase expression vector with a histidine tag (6 * His), the expression vector is pET-28a, and introducing into a host cell to induce expression; a high-purity enzyme is obtained by adopting methods such as affinity chromatography and gel filtration chromatography, and enzyme activity determination is carried out. Based on an amino acid sequence of Salsolinol synthetase, an efficient in-vitro expression vector is constructed, and high-purity enzyme is prepared.

The invention provides fusion protein containing snake venom protein and application of the fusion protein in biosynthesis of stable isotope labeled snake venom protein, and belongs to the technical field of genetic engineering and protein preparation. The fusion protein comprises a 6-poly-histidine tag, a fusion tag, a restriction enzyme cutting site of WELQ protease and snake venom protein which are connected in sequence. According to the fusion tag, the solubility of the snake venom protein fusion protein can be improved; the 6-poly-histidine tag and the fusion tag can be removed through enzyme digestion of WELQ protease, the enzyme digestion removal effect is good, and the natural structure and activity of the snake venom protein can be guaranteed; besides, a culture medium containing a unique nitrogen source or a unique carbon source labeled by an isotope is used for carrying out induction culture on recombinant bacteria for expressing the fusion protein, the fusion protein containing the target snake venom protein is subjected to induction expression, purification, WELQ protease digestion and the like are carried out, and the stable isotope labeled snake venom protein with the purity reaching 95% or above and the labeling efficiency exceeding 91% can be obtained.

To provide a high-affinity monoclonal antibody for a His-tag added to the C terminus of membrane protein.SOLUTION: The present invention provides a monoclonal antibody for a histidine tag (His-tag) or an antigen-binding fragment thereof, wherein the monoclonal antibody recognizes, as an epitope, a His-tag added to the C terminus of a membrane protein.SELECTED DRAWING: None

The application discloses a histidine tag diversity nucleic acid aptamer and application thereof, and belongs to the technical field of biological processing. The nucleotide sequence of the histidine tag diversity nucleic acid aptamer is shown in SEQ ID NO. 3, or SEQ ID NO. 4, or SEQ ID NO. 5, or SEQ ID NO. 6. The application also discloses an application of the histidine tag diversity nucleic acid aptamer in preparation of a biosensor element for targeted recognition of a histidine tag-containing protein or polypeptide. The application also discloses an application of the histidine tag diversity nucleic acid aptamer in qualitative analysis, quantitative detection and separation and purification of the histidine tag-containing protein or polypeptide. The histidine tag diversity nucleic acid aptamer is obtained by taking HisA1-T63 aptamer as an initial chain, preliminarily improving the aptamer through sequence truncation, and repositioning a functional module to a loop region for diversity modification, thereby expanding the structural diversity of the histidine tag nucleic acid aptamer.

A high-mannose antibody-specific affinity material, a preparation method therefor and a use thereof. Provided are a lectin variant comprising (a) a histidine tag and (b) a cysteine-containing segment, added to the C-terminus of a reference lectin; a nucleic acid molecule encoding the lectin variant, and a vector and a cell containing the nucleic acid molecule; a composition and a matrix comprising the lectin variant; and a use of the lectin variant for reducing or removing a high-mannose antibody from a sample. The lectin variant has a specific affinity for high-mannose antibodies, and can effectively bind to high-mannose antibodies formed during antibody production, to remove high-mannose byproducts contained in recombinant antibodies, thereby effectively promoting and achieving required antibody purification in downstream stages of production.

Use of a TEV protease (wild type or mutant) suitable for removal from a reaction mixture is disclosed wherein the TEV protease exhibits an amphiphilic tag, including a chitin binding domain (CBD) tag and a histidine tag, preferably wherein the CBD is prior to the N-terminus of the protease and prior to the CBD tag is the histidine tag, and wherein the CBD tag is the histidine tag. Preferably, the histidine tag is a 6-mer histidine tag; and optionally, a first linker, preferably a Gly-Ser linker, and more preferably a 6-mer Gly-Ser linker, is also included between the labels. A second linker, also preferably a Gly-Ser linker, may also be after the CBD tag and before the protease moiety. In some embodiments, such a joint is not present, while in other embodiments, only one such joint is present.

The invention relates to the technical field of biology, and discloses a recombinant N-acetylglucosamine-1-phosphate uridine transferase (GlmU) mutant and a preparation method thereof. The sequence of the recombinase is formed by connecting an N-acetylglucosamine-1-uridine phosphate transferase (GlmU) mutant (L113V-V172I) from Azotobacter chroococcum, an N-terminal histidine tag (His-tag) and a small ubiquitin-like modified protein tag (SUMO-tag) in series. The invention further discloses a preparation method of the recombinase. Compared with a recombinant wild type N-acetylglucosamine-1-uridine phosphate transferase with the same source, the recombinant N-acetylglucosamine-1-uridine phosphate transferase mutant has higher activity which is 1.5 times of that of the recombinant wild type and higher stability, and the residual activity of the mutant is 66.5% after the mutant is placed at room temperature for 5 days, so that the mutant has a good application prospect in the field of N-acetylglucosamine-1-uridine phosphate transferase. And the soluble expression quantity of the recombinant mutant N-acetylglucosamine-1-uridine phosphate transferase is increased by 5 times.

The present invention belongs to, but is not limited to, the field of genetic engineering technology and discloses a Japanese eel Activin A recombinant protein, its expression method, and application. The Japanese eel Activin A recombinant protein comprises: the amino acid sequence of the Japanese eel Activin A mature peptide, a 6× histidine tag at the N-terminus, and a SUMO solubilizing polypeptide; its amino acid sequence is SEQ ID NO: 1, and the nucleotide sequence of the gene encoding the Japanese eel Activin A recombinant protein is SEQ ID NO: 3. The present invention constructs the prokaryotic expression vector pET-His-SUMO-ActivinA for Japanese eel Activin A for the first time, which can produce an Activin A recombinant protein with an amino acid sequence consistent with the Japanese eel Activin A mature peptide, which can be applied to the research on ovarian development regulation and artificial reproduction of Japanese eels.

A method for preparing an antibody-drug conjugate. The antibody-drug conjugate is formed by means of site-directed conjugation on the basis of an N-glycosylation site of an Fc region of an antibody. The method comprises: (1) providing a donor containing an oxazoline oligosaccharide, an antibody containing a GlcNAc motif, and an immobilized endoglycosidase having a glycoside transfer activity; and (2) covalently linking the activated donor containing the oxazoline oligosaccharide to the antibody containing the GlcNAc motif by means of the catalytic action of the endoglycosidase; therefore, one-step conjugation is realized. The present invention also relates to an endoglycosidase fusion protein, which comprises a covalently linked endoglycosidase, a Halo tag, and / or a His tag. The present invention also relates to an immobilized endoglycosidase fusion protein obtained by means of immobilizing an endoglycosidase fusion protein on a support, a prepacked column filled with the immobilized fusion protein, and a method for purifying an antibody conjugate by using the immobilized endoglycosidase fusion protein.

A method of generating a supramolecular structure is disclosed.The method comprises (a) contacting a divalent or trivalent metal cation with at least one protein-based molecule comprising at least two histidine tags under conditions that generate the supramolecular structure; and (b) isolating the supramolecular structure. Uses of the supramolecular structures are also disclosed.

The invention pertains to His tagged FimHLD R60P protein for use as a medicament, in particular as an antigen in a vaccine to protect against an infection with E. coli.

The invention belongs to the field of biological medicine, and particularly relates to a protein purification method based on an anti-His tag monoclonal antibody. The antibody can recognize histidine tags with high specificity, an affinity chromatography medium prepared with the antibody as a ligand can efficiently purify His tag protein, the problem that metal ions fall off in traditional metal chelating chromatography can be effectively solved, and non-specific adsorption of impure protein is remarkably reduced. The purification method based on the medium has strong targeting capture capability, can greatly improve the final purity and yield of the protein with the histidine tag, and provides a reliable solution for obtaining the high-purity protein.

The invention discloses an HlyA secretion system for increasing the secretion amount of substrate protein and a construction method and application thereof.The HlyA secretion system comprises a first component, a second component and a third component, the first component comprises an inner membrane transporter HlyB and a membrane interstitial adaptor protein HlyD, and the inner membrane transporter HlyB and the membrane interstitial adaptor protein HlyD are obtained by expressing modified hlyBD operons; according to the modified hlyBD operon, a nucleotide sequence for coding a hexa-polyhistidine tag is inserted behind an hlyD gene initiation codon in the hlyBD operon; and a second component: an outer membrane channel protein TolC derived from a host cell. According to the invention, the HlyD protein is specifically modified, so that the secretion amount of the HlyA secretion system to the substrate protein is obviously increased.

The invention relates to a nanoparticle (1) having core (2), a first surface functionalization (4), and a second surface functionalization (5). The core (2) comprises or consists of a metal, preferably silver. An inorganic coating (3) is arranged around the core (2). The coating (3) preferably comprises or consists of gold. The first surface functionalization (4) is adapted to provide colloidal stability of the nanoparticle (1) in, preferably aqueous, solvents (19). The first functionalization (4) substantially prevents non-specific binding of macromolecules (55), in particular macromolecules including proteins, DNA, and / or RNA. The second surface functionalization (5) includes one of a binding site for a binding partner, preferably a binding site for a poly-histidine tag of a biomolecule (55), and a biomolecule, preferably a protein.

This invention discloses a metal ion-driven meliosteum peptide nanoassembly, its preparation method, and its applications, relating to the field of agricultural biotechnology. The meliosteum peptide nanoassembly is formed by the self-assembly of a hexahistidine-tagged meliosteum peptide with divalent metal ions through coordination. The average particle size of the meliosteum peptide nanoassembly is 20 nm–30 nm. The meliosteum peptide nanoassembly obtained by this invention through the self-assembly of a hexahistidine-tagged meliosteum peptide with zinc ions exhibits excellent antibacterial, anti-biofilm activity, stability, and biocompatibility, and can be used to control plant bacterial diseases caused by Xanthomonas and other fungi.

The present application relates to the technical field of biology, and particularly relates to a method for stably improving horseradish peroxidase-labeled streptavidin titer. The method provided by the present application is to design streptavidin with different histidine tag lengths, and then couple with sodium periodate-oxidized horseradish peroxidase, so that high-titer horseradish peroxidase-labeled streptavidin can be obtained. The present application also discloses application of the enzyme-labeled conjugate in a magnetic microsphere platform streptavidin-biotin system. Experimental results prove that the method provided by the present application can stably prepare high-titer and low-background enzyme-labeled conjugate, and the enzyme-labeled conjugate can be widely applied in the streptavidin-biotin system.

The present application relates to a kind of monoclonal antibody that can identify human Mucin6 antigen, its preparation method and its use in immunodetection.The above technical solution selects the amino acid of 1950-2050 of Mucin6 protein as antigen peptide, codon optimization becomes the gene fragment suitable for expressing in escherichia coli BL21, and finally the recombinant protein containing Mucin6 protein fragment and histidine tag.The recombinant protein is immunized to mouse, and after cell fusion, screening and subcloning, obtain the mouse hybridoma cell strain 37D10 and the anti-Mucin6 protein monoclonal antibody secreted by the cell strain.The antibody obtained by the present application has high specificity, sensitivity, and can specifically recognize the cell expressing Mucin6 protein, and is suitable for immunological detection, especially immunohistochemical detection.

The invention relates to a p-toluenesulfonyl functionalized fluorescent probe capable of being specifically combined with a histidine label and application of the p-toluenesulfonyl functionalized fluorescent probe in single-molecule FRET (Fluorescence Resonance Energy Transfer) research. The probe is based on a Cyanine 5 dye, and can realize covalent binding with a protein with a His-tag by performing chemical modification on toluenesulfonyl. Compared with a traditional Ni < 2 + >-NTA non-covalent fluorescent probe, the probe provides higher binding stability and site specificity, and is suitable for high-resolution single-molecule fluorescence imaging of protein. The invention further establishes a protein fluorescence labeling strategy which is suitable for smFRET analysis and is universal, simple and convenient to operate and stable in labeling, and a novel technical means is provided for exploring protein conformation change and a dynamic regulation and control mechanism.

The application discloses a method for expressing BirA enzyme by using prokaryotic Escherichia coli and purifying the BirA enzyme, and relates to the technical fields of genetic engineering and protein engineering. A recombinant expression vector for expressing the BirA enzyme is a pET-28A-BirA plasmid which is constructed by inserting a BirA enzyme coding gene into a multiple cloning site of a pET-28A vector. An 8× histidine tag coding nucleotide sequence is fused to a C terminal of the BirA enzyme coding gene. The nucleotide sequence of the BirA enzyme coding gene is shown as SEQ ID NO:1. The prokaryotic expression system is simple in culture condition, short in cycle, and low in cost, and is suitable for large-scale preparation. The 8× histidine tag is introduced into the C terminal of the BirA enzyme gene, so that the expression product can be purified by one-step nickel column affinity chromatography, and the purification process is simple and high in efficiency.

The present invention relates to a method for isolating and purifying a protein with at least two histidine tags, in particular to a method for isolating and purifying a protein with at least two histidine tags in solution by using cations.

Disclosed is using a TEV protease (wild type or mutant) suited for removal from a reaction mixture, wherein the TEV protease displays a dual affinity tag including a chitin binding domain (CBD) tag and a histidine tag, preferably where the CBD tag precedes the N-terminus of the protease and the CBD tag is preceded by the histidine tag, which is preferably a 6-mer histidine tag; and optionally further including linkers, preferably Gly-Ser linkers, and more preferably a 6-mer Gly-Ser linker, between the tags. A linker, also preferably a Gly-Ser linker, can also follow the CBD tag and precede the protease portion. In certain embodiments, no such linkers are present and in other embodiments, only one such linker is present.

The invention belongs to but is not limited to the technical field of gene engineering, and discloses an anguilla japonica Activin B recombinant protein and an expression method and application thereof, the anguilla japonica Activin B recombinant protein comprises an anguilla japonica Activin B mature peptide amino acid sequence, a 6 * histidine tag at the N end and SUMO dissolution promoting polypeptide; the amino acid sequence of the anguilla japonica Activin B recombinant protein is SEQ ID NO: 1, and the amino acid sequence of the anguilla japonica Activin B mature peptide is SEQ ID NO: 2. The prokaryotic expression vector pET-His-SUMO-Activin B of the Japanese eel Activin B is constructed for the first time, the Activin B recombinant protein with the amino acid sequence consistent with the mature peptide of the Japanese eel Activin B is obtained, and the Activin B recombinant protein can be applied to ovarian development regulation and artificial propagation research of the Japanese eel.

The application discloses a novel coordination peptide QEY127 and application thereof in assembling a luminescent material with a rare earth ion. The coordination peptide QEY127 is composed of one start codon coding methionine (M), one 6-polyhistidine tag (6X His) and 10 QSEPGDPGEPSY (QEY12), and has a length of 127 amino acid residues; the coordination peptide QEY127 gene is obtained through a whole gene synthesis method, and the codon composition is optimized. The yield of the coordination peptide QEY127 is 100-1200 mg / L of fermentation liquor, and the purity is 82-95%. The coordination peptide QEY127 has the characteristics of glutamine transaminase (TG enzyme) catalyzed crosslinking, high elasticity and formation of a luminescent coordination compound with a rare earth metal, and has a wide application prospect in the fields of biological medical treatment and luminescent materials.

Disclosed herein are compositions and constructs related to a polypeptide, PT-X'n-PTA-Hm (1 ), or pharmaceutically acceptable salts thereof, wherein PT is a peptide transport or fragment thereof; X'n is linker comprising a triazole moiety, n = 0 or 1; PTA is a peptide therapeutic agent selected from the group consisting of a modified semaglutide, a modified tirzepatide, caplacizumab, ozoralizumab; and Hm is a histidine tag where m is 0 to 6; as well as uses thereof.

The invention provides an antibody SEC55, a fusion protein SEC55-vHRP, a preparation method and an application. The fusion protein comprises an IgG antibody signal peptide, a hemagglutinin tag, the antibody SEC55, a connecting peptide, horse radish peroxidase and a histidine tag. The fusion protein can be used for detecting staphylococcus aureus enterotoxin C in food. The fusion protein SEC55-vHRP is provided with a horse radish peroxidase label, so that secondary antibody incubation is not needed, subsequent chromogenic reaction can be directly carried out after primary incubation is finished, the detection time is shortened, and the fusion protein SEC55-vHRP has a wide application prospect.

Either wild type or mutant Serratia Marcescens Nuclease (“SMN”) is engineered to display a C-terminal Chitin Binding Domain (CBD-tag), followed, at the C-terminus side of the CBD-tag, by a poly-histidine tag (His-tag), where the His-tag is preferably a 6-mer and preferably is preceded by a Gly-Ser linker, thereby generating a recombinant SMN protein that retains dual affinity tags (a CBD-tag and a His-tag) at the C-terminus, to make it easily removed from a reaction solution following digestion of nucleic acids in the reaction mixture. It can also be used for binding SMN to a solid support for use in nucleic acid digestion in a sample contacted with the solid support.