150 results about "Polypeptide chain" patented technology

This invention provides a tetrahedral antibody comprising a first, second, third, and fourth domain, wherein the first and second domains are Fab or Fc domains; wherein each of the first and second domains comprise a first polypeptide chain comprising a first N-terminus of the domain, and a second polypeptide chain comprising a second N-terminus of the domain; wherein the first N-terminus of the first domain and the first N-terminus of the second domain are joined to each other by a non-peptidyl linkage, which can be a covalent linkage or a non-covalent linkage between first and second dimerizing polypeptides attached to the first N-termini of the first and second domains, respectively; and wherein the third and fourth domains are attached at their respective C-termini to the second N-termini of the first and second domains, respectively, or the N-termini of the first and second dimerizing polypeptides.

The invention discloses a preparation method of a polymer vesicle capable of crossing a blood brain barrier, and belongs to the field of high polymer materials and medical engineering. The preparation method of the polymer vesicle capable of crossing the blood brain barrier comprises the following steps: synthesizing an amphiphilic block copolymer by utilizing ring-opening polymerization reaction of polycaprolactone and anhydride in an amino acid ring, then assembling the polymer into the polymer vesicle, and modifying a monoclonal antibody of a transferrin receptor on a polypeptide chain. The polymer vesicle prepared by the invention is simple and convenient in preparation process, short in period, good in stability, good in biocompatibility and good in biodegradability, can be used as an excellent carrier of chemotherapeutic drugs, and can effectively realize drug delivery of targeting brain tumor cells across a blood brain barrier. Compared with a commercial drug delivery carrier, the polymer vesicle has the advantage that the permeability of the drug in a bionic blood brain barrier and the targeted uptake rate of brain tumor cells are remarkably improved.

The invention discloses a method for separating an egg white polypeptide chain by adopting a coupling membrane, and particularly relates to the field of egg white polypeptide chains, the method comprises the following steps: S1, mixing fresh egg white with a buffer solution, adjusting the initial acid-base environment and initial temperature of a system, and measuring key basic parameters after dispersion treatment; s3, introducing the pretreated egg white liquid into a first-stage membrane assembly, monitoring separation process parameters, obtaining interception efficiency, dynamically adjusting operation parameters, and enabling permeate liquid to enter a second-stage membrane assembly; s7, monitoring system environment parameters and polypeptide activity, obtaining an activity retention rate, dynamically adjusting supply parameters, and maintaining the polypeptide activity; s8, classifying and collecting products according to molecular weight intervals, evaluating comprehensive separation efficiency, completing separation and verifying product indexes; by constructing an ultrafiltration membrane-nanofiltration membrane-reverse osmosis membrane three-stage coupling separation system and combining a dynamic parameter adjustment mechanism based on interception efficiency, separation selectivity and refined purity, the purity and separation efficiency of a polypeptide product are remarkably improved.

The invention provides semeglutide, which is synthesized by adopting the following method, and the specific steps are as follows: 1) segmenting the main chain of semeglutide into three polypeptide fragments: 7-14 sites, 15-22 sites and 23-37 sites; (2) respectively preparing the 7-14-site fragments, the 15-22-site fragments and the 23-37-site fragments through solid-phase synthesis; 3) connecting the 7-14-site fragment with the 15-22-site fragment to form a 7-22-site fragment, and activating the C end of the fragment into active ester; (4) selectively removing an Alloc protecting group of Lys26 in the 23-37-site fragment, and then carrying out fatty acid modification to obtain a modified 23-37-site fragment; 5) in a liquid phase system, coupling the activated 7-22-site fragment and the modified 23-37-site fragment according to a molar ratio of 1: (0.6-1.4) to form a complete polypeptide chain; and 6) removing the protecting group and purifying to obtain a semaglutide finished product. The method provided by the invention can effectively realize high-purity, high-yield and low-cost synthesis of the semeglutide bulk drug.

Provided herein are trispecific and / or trivalent binding proteins comprising four polypeptide chains that form three antigen binding sites that specifically bind one or more target proteins, wherein a first pair of polypeptides forming the binding protein possess dual variable domains having a cross-over orientation, and wherein and a second pair of polypeptides possess a single variable domain forming a single antigen binding site. In some embodiments, the binding proteins comprise a binding site that binds a CD28 polypeptide, a binding site that binds a CD3 polypeptide, and a binding site that binds a third polypeptide, such as a tumor target protein. In some embodiments, the binding proteins comprise four polypeptide chains that form three antigen binding sites that specifically bind one or more HIV target proteins. The disclosure also relates to methods for making trispecific and / or trivalent binding proteins and uses of such binding proteins.

Provided herein are compositions comprising trispecific and / or trivalent binding proteins comprising four polypeptide chains that form three antigen binding sites that specifically bind one or more HIV target proteins or one or more T-cell receptors, wherein a first pair of polypeptides forming the binding protein possess dual variable domains having a cross-over orientation and wherein a second pair of polypeptides forming the binding protein possess a single variable domain. Also provided herein are methods for making trispecific and / or trivalent binding proteins and uses of such binding proteins for the treatment and / or prevention of HIV / AIDS.

Provided herein are trispecific and / or trivalent binding proteins comprising four polypeptide chains that form three antigen binding sites that specifically bind one or more target proteins, wherein a first pair of polypeptides forming the binding protein possess dual variable domains having a cross-over orientation, and wherein and a second pair of polypeptides possess a single variable domain forming a single antigen binding site. In some embodiments, the binding proteins comprise a binding site that binds a CD28 polypeptide, a binding site that binds a CD3 polypeptide, and a binding site that binds a third polypeptide, such as a tumor target protein. In some embodiments, the binding proteins comprise four polypeptide chains that form three antigen binding sites that specifically bind one or more HIV target proteins. The disclosure also relates to methods for making trispecific and / or trivalent binding proteins and uses of such binding proteins.

The invention provides a preparation method of a recombinant cell, the recombinant cell and application of the recombinant cell, and relates to the technical field of biology. A target protein expressed by the recombinant cell contains one, two, three or four polypeptide chains; the preparation method comprises the following steps: integrating exogenous polynucleotides for coding a target protein into a genetic material of a starting cell in a site-specific manner, wherein each exogenous polynucleotide for site-specific integration contains coding genes of all polypeptide chains of the target protein; each exogenous polynucleotide contains at least four expression cassettes, and each polypeptide chain is encoded by at least one expression cassette. The preparation method is simple to operate, coding genes of all polypeptide chains can be integrated into genetic materials of starting cells at a time, and the expression quantity of foreign proteins of the recombinant cells obtained through the preparation method is high.

This application relates to facilitating the selective binding between modified VH and VL domains by introducing amino acids with complementary charges into the two domains at novel positions within these domains. These modifications are particularly useful in the design and generation of multispecific antibodies, such as bispecific antibodies, where charge-pair mutations in VH and VL domains can facilitate desired pairing between specific heavy- and light-chain polypeptides. These charge-pair mutations can be used alone or in combination with additional strategies to promote correct pairing of polypeptide chains.

This invention provides an antibody composition with improved stability, exhibiting reduced fragmentation of the antibody polypeptide chain during manufacturing and subsequent storage. [Solution] This disclosure relates to improved compositions and methods for treating T cell-mediated diseases and disorders (e.g., autoimmune disorders, graft-versus-host diseases, and graft rejection). Provided are antibody-containing anti-αβTCR binding polypeptides comprising at least one amino acid substitution or modification that enhances the stability of the binding polypeptide by reducing fragmentation of the light chain variable region. Methods provided herein generally involve administering an effective amount of a stabilized, humanized binding polypeptide specific to the alpha-beta T cell receptor (αβTCR) to a subject in need thereof.

The invention provides a three-specificity immune cell adapter-cytokine fusion protein for malignant tumor immunotherapy as well as a preparation method and application of the three-specificity immune cell adapter-cytokine fusion protein. The fusion protein comprises a first binding domain, a second binding domain and a cytokine structural domain which are covalently linked to form a single polypeptide chain or polypeptide compound. The first binding domain is specifically bound with a tumor associated antigen, and the target spot of the first binding domain comprises but is not limited to KK-LC-1, MSLN, HER2, Claudin18.2, Claudin6 and PSMA; the second binding domain is specifically bound with a CD3 protein complex on the surface of the T cell; the cytokine domain is IL2, IL15, IL12, IL21 or a functional variant thereof. The invention also relates to a nucleic acid molecule for coding the fusion protein, an expression vector and application thereof. The fusion protein can be used for immunotherapy of malignant tumors such as colon cancer, gastric cancer, breast cancer, liver cancer, lung cancer and cervical cancer, and has a good application prospect. The invention effectively solves the problems of insufficient T cell activation and limited killing in solid tumor immunotherapy in the prior art.

An affinity carrier may have improved alkali resistance. An immunoglobulin-binding protein containing a mutant polypeptide chain, as well as an affinity carrier containing a solid-phase carrier to which the immunoglobulin-binding protein is bound, may be a mutant polypeptide chain having an amino acid sequence having at least 85% identity to an amino acid sequence indicated by any of SEQ ID NO: 1-6 and 57-62, having a predetermined mutation, and having immunoglobulin-binding activity.

This invention relates to protein-based adhesives that are capable to adhere to a substrate in a dry, wet, moist, or an aqueous environment. Particularly, said adhesives comprise a crosslinking agent and an elastin-like polypeptide (ELP) that contain tyrosine, lysine, cysteine, dihydroxyphenylalanine (DOPA) or trihydroxyphenylalanine (TOPA) amino acid residue, or a combination thereof, on the polypeptide chain of said ELP. Among others, the adhesives disclosed herein may find broad applications in medical treatments and surgical operations. Compositions and methods of use are within the scope of this application.

A recombinant hemoglobin, a nucleic acid encoding the recombinant hemoglobin, and a preparation method therefor are provided to address the current problems of complex processes, high production costs, and low yields that exist for improving a hemoglobin having a stable tetrameric structure. The recombinant hemoglobin comprises: two or more units of recombinant hemoglobins, the units of recombinant hemoglobins each comprise four polypeptide chains, and the polypeptide chains are two α chains and two β chains. The amino acid sequences of the four polypeptide chains of each unit of recombinant hemoglobin are linked by means of intra-unit linker peptides to form the unit of recombinant hemoglobin, and two or more of the units are linked by means of inter-unit linker peptides.

The invention discloses a bispecific antibody targeting T cells and Her2 positive cells and a fusion protein connected in series with 4-1BBL. Belongs to the technical field of biology. The fusion protein is of a heterotetramer structure formed by connecting two similar heavy polypeptide chains and two similar light polypeptide chains through disulfide bonds, wherein the similar heavy polypeptide chains comprise a heavy chain variable region of a Her2 targeting antibody, a human IgG1 Fc region and a human 4-1BBL extracellular region; the light polypeptide-like chain comprises a light chain variable region of a Her2 targeting antibody, a human antibody light chain constant region and a single chain variable region fragment of a CD3 targeting antibody. The fusion protein can specifically bind to Her2 positive tumor cells and CD3 molecules on the surfaces of T cells at the same time, and provides a key co-stimulation signal by using 4-1BBL connected in series, so that the killing function of the T cells is efficiently activated and enhanced in the local part of the tumor. The fusion protein provides a novel candidate strategy with stronger curative effect, more lasting effect and better safety for immunotherapy of Her2 positive tumors.

The invention discloses a protein sequence phosphorylation site prediction method and system, computer equipment and a storage medium, and relates to the technical field of protein sequence phosphorylation site prediction.The protein sequence phosphorylation site prediction method includes the steps that data collection is conducted on an amino acid sequence of a protein and a corresponding phosphorylation site, preprocessing is conducted in an automatic labeling mode, and a prediction result is obtained; dividing the protein sequence into a plurality of polypeptide chains through sliding window calculation; the method comprises the following steps: coding an amino acid sequence based on a BERT protein language model, extracting protein information features, calculating an emission score and a transfer score by taking a conditional random field (CRF) as a decoder, capturing regional distribution and a tandem effect of phosphorylation sites, and carrying out loss calculation by taking a negative likelihood logarithm (NNL) as a loss function, protBERT is adopted as a main framework for extracting protein sequence information to carry out establishment and training of a phosphorylation prediction model; and carrying out phosphorylation prediction through the phosphorylation prediction model. According to the method, the labor cost and the time cost are greatly reduced.

A protein molecule that includes interleukin 12a (IL12a), interleukin 12b (IL12b), a first factor and a second factor located in the same polypeptide chain that can be used for treating tumors.

The invention discloses a method for modifying polypeptide with decarboxylated boric acid and trifluoroboric acid, which comprises the following steps: under a solid phase condition, carrying out active esterification reaction on polypeptide I under a condition (i) to prepare active esterified polypeptide II; then reacting the active esterified polypeptide II with a boric acid source under the action of a condition (ii) to form a borated polypeptide III; finally, under the condition (iii), the boric acid polypeptide III is subjected to fluorination treatment, and the trifluoroborate polypeptide IV is obtained. According to the method disclosed by the invention, decarboxylation and boric acid acidification of glutamic acid or aspartic acid residues in a polypeptide chain can be specifically realized, and controllable introduction of a trifluoroboric acid group is further completed.

The invention relates to aminoacyl-tRNA synthetases that aminoacylate tRNA with 2-Aminoisobutyric acid (Aib), thus enabling the incorporation of the Aib into a growing polypeptide chain during translation, e.g. in eubacterial host cells such as E. coli. For example, but not limited to, the invention relates to new aminoacyl-tRNA synthetases and the uses hereof, as well as a method for producing polypeptides that contain one or more Aib.

The present application relates to the field of immunotherapy, more particularly to the field of chimeric antigen receptors (CARs). Currently, second and third generation CAR designs are quite rigid in that they combine fixed costimulatory domains in cis on the same intracellular protein domain. Trans signaling is not equivalent as costimulatory receptors have different expression levels or stoichiometry. Here, a ‘mix and match’ approach is proposed where different signaling and costimulatory domains are present on separate chains within the same CAR complex, allowing increased flexibility and control of the nature and strength of the CAR-generated signal. Also proposed are polynucleotides, vectors encoding the transmembrane polypeptide chains and cells expressing such CARs. These cells are particularly suitable for use in immunotherapy, and strategies to treat diseases such as cancer using these cells are also provided.

The application belongs to the technical field of biological medicine, and relates to an antibacterial polypeptide, a composition and application thereof. The amino acid sequence of the antibacterial polypeptide is shown in SEQ ID NO. 1: KWKIKWPVKWFKM-NH2. Experiments show that the antibacterial polypeptide has broad-spectrum antibacterial activity on gram-positive bacteria and / or gram-negative bacteria, and simultaneously has low cytotoxicity and low hemolyticity. The antibacterial polypeptide provided in the application is composed of 14 amino acids, the polypeptide chain is short, the molecular weight is small, and the antibacterial polypeptide is easy to be artificially synthesized, is a small-molecule polypeptide with high application value, and can be used for preparing a novel antibacterial agent, and has wide application prospects.

This invention proposes a method for screening bisphenol A-specific peptides using molecular simulation, belonging to the field of food safety technology. The method includes the following steps: 1) Through protein stacking and molecular docking, the molecular structure and interactions of bisphenol A-protein cocrystal compounds in a protein structure database are comprehensively analyzed to obtain the receptor protein and the original parent chain; 2) Based on the original parent chain obtained in step 1), the parent peptide is obtained by truncation of the parent peptide segment by analyzing the main active amino acids in the molecular docking results; 3) By performing virtual amino acid mutations on the parent peptide obtained in step 2), a peptide library specifically binding to bisphenol A is constructed, and molecular dynamics is used for preliminary screening of the peptides; 4) The peptide chains screened in step 3) are used as specific recognition elements, and peptides labeled with fluorescein isothiocyanate are used to form specific recognition probes. The specific recognition probes are mixed with bisphenol A, and the peptide sequences with the strongest specific binding ability to bisphenol A are screened based on the different fluorescence differences. This invention is mainly applied to the screening of specific recognition elements for toxic and harmful small molecules, active ingredients, and functional factors. This method avoids the complex preparation steps of antibodies and the cumbersome screening process of aptamers, achieving high-throughput design of specific recognition elements.

A multi-domain fusion protein molecule is composed of an antibody single-chain molecule without an immune effect and a polypeptide receptor molecule, which specifically binds to pMHC epitope, or component part thereof or fragment thereof. These protein domains is close to the natural state, can be mixed to form a fusion protein complex molecule having a biological function, and can avoid the risk of immunogenicity caused by introducing artificial flexible peptide chains to link each domain into a single polypeptide chain molecule.

The present invention provides recombinant bispecific antibodies designed to bind to a surface antigen on target cells and to an activating component on immune cells such as T cells. The bispecific antibodies comprise two polypeptide chains that contain Fv and Fab as antigen¬binding fragments and a modified Fc region to facilitate heterodimer formation. In one embodiment, the bispecific antibodies further comprise protease cleavage sites and / or motifs that would cause steric occlusion of the antigen binding sites so that the antibodies would be activated only in a specific environment, e.g. in the vicinity of a tumor. In another embodiment, the bispecific antibodies comprise modified sequences that confer reduced binding affinity to CDS and / or cross-reactive binding to CDS on cells from different species.

Disclosed is a printing ink including a fixing agent including a peptide polymer (having a polypeptide chain), a liquid medium, and a colorant. Also disclosed is a method of manufacturing a printed matter, the method comprising: a step of forming a film containing a printing ink on a substrate by a printing process; and removing the solvent from the film to form a printed film containing the fixing agent and the coloring agent. The polypeptide chain may also include an artificial protein.

The present invention provides a gel temporary plugging agent and its preparation method and application, which belong to the field of oilfield chemical technology. The gel temporary plugging agent provided by the present invention has a three-dimensional network structure formed by cross-linking animal proteins, and can be degraded into linear polypeptide chains in acid under low temperature conditions, thereby achieving a temporary plugging effect; by introducing a reinforcing agent structural unit for enhancement, the plugging performance of the gel temporary plugging agent is ensured, so that it can achieve the plugging of low-temperature reservoirs. The results of the embodiment show that the hardness of the gel temporary plugging agent prepared by the present invention can reach 42.0N, the elasticity can reach 9.50mm, and the plugging pressure can reach 24.69MPa at a permeability of 1105.2mD; the degradation time can be controlled at 1.3 to 4.1d.

Provided is a bone regeneration material that can provide sufficient therapeutic effects when applied to a bone defect site. The bone regeneration material according to the present invention contains a protein (A). The protein (A) has a polypeptide chain (Y) and / or a polypeptide chain (Y'). The total number of the polypeptide chain (Y) and the polypeptide chain (Y') in the protein (A) is 1-100. The polypeptide chain (Y) includes 2-200 contiguous repeats of an amino acid sequence (X), the amino acid sequence (X) being at least one of: the VPGVG sequence (1), which is the amino acid sequence represented by SEQ ID NO: 1; the GVGVP sequence (4), which is the amino acid sequence represented by SEQ ID NO: 4; and the GAHGPAGPK sequence (3), which is the amino acid sequence represented by SEQ ID NO: 3. The polypeptide chain (Y') is derived from the polypeptide chain (Y) by substituting 5% or less of the amino acid residues with lysine and / or arginine residues, and the total number of the lysine and arginine residues is 1-100.

The invention discloses a compound comprising or consisting of a polypeptide with the general formula (I): X0GX1X2GX3X4X5GX6X7X8GX9X10X11X12X13X14, wherein G is glycine; X0 is present or not and, if present, is an amino acid linker; X1 is N or S, wherein N is asparagine and S is serine; X2 is S or T, wherein S is serine and T is threonine; X3 is present or not and, if present, is S, wherein S is serine; X4 is present or not and, if present, is G, wherein G is glycine; X5 is a basic polypeptide stretch consisting of 5 basic amino acid residues selected from R and K, wherein R is arginine and K is lysine, preferably wherein X5 comprises at least 3 K amino acid residues, especially wherein X5 is KKKKK or KRKKK; X6 is a basic amino acid residue selected from R and K, wherein R is arginine and K is lysine, preferably wherein X6 is K; X7 is S or L, wherein S is serine and L is leucine; X8 is present or not and, if present, is a polypeptide stretch consisting of the amino acid sequence GLGS, wherein G is glycine, L is leucine and S is serine; X9 is a basic polypeptide stretch consisting of 3 basic amino acid residues selected from R and K, wherein R is arginine and K is lysine, preferably wherein X9 comprises at least 2 K amino acid residues, especially wherein X9 is KKK or KKR; X10 is present or not and, if present, is L or a polypeptide stretch consisting of the amino acid sequence DPL or DPC, wherein L is leucine, D is aspartic acid, P is proline, and C is cysteine; X11 is present or not and, if present, is a polypeptide stretch consisting of the amino acid sequence LR or GSGL, wherein L is leucine, R is arginine, G is glycine, and S is serine; X12 is present or not and, if present, is a basic polypeptide stretch with at least 20% basic amino acid residues selected from K and R and at least a P residue, preferably wherein X12 is selected from KYKPKL, KYKPKLGT, or GX3X4X5GX6X7X8GX9X10, wherein K, R, P, L, G, T, X3, X4, X5, GX6, X7, X8, GX9, and X10, are CA defined as above and wherein Y is tyrosine; X13 is present or not and, if present, is a polypeptide stretch consisting of the amino acid sequences GS, GST, GST, GSG, GSTG, or GSGL, wherein G, S, T and L are defined as above; X14 is present or not and, if present, is an amino acid linker; wherein the polypeptide has a length from 20 to 75 amino acid residues, preferably from 24 to 65 amino acid residues, especially from 25 to 60 amino acid residues.

The present invention relates to a bispecific polypeptide molecule comprising a first polypeptide chain and a second polypeptide chain providing a binding region derived from a T cell receptor (TCR) being specific for a major histocompatibility complex (MHC)-associated peptide epitope, and a binding region derived from an antibody capable of recruiting human immune effector cells by specifically binding to a surface antigen of said cells, as well as methods of making the bispecific polypeptide molecule, and uses thereof.

The invention discloses a PD-L1 cell targeting fusion protein connected in series with a TGFBR2 extracellular domain, IL-2 and a receptor thereof, and an application thereof. Belongs to the technical field of biology. The fusion protein provided by the invention is a heterotetramer formed by connecting two similar heavy polypeptide chains and two similar light polypeptide chains through a disulfide bond. The fusion protein realizes triple functions through a single molecule: tumor specific localization is realized through PD-L1 targeting VHH (Vascular Haemophilus Haemophilus Haemophilus Haemophilus Haemophilus Haemophilus Haemophilus Haemophilus Haemophilus Haemophilus Haemophilus); an immunosuppressive factor TGF-beta in a tumor microenvironment is neutralized through TGFBR2 ECD; effect immune cells expressing a medium affinity IL-2 receptor are selectively activated and amplified by the combination of IL-2 and IL-2R alpha. The PD-L1 inhibitor provided by the invention overcomes the multiple problems of limited curative effect of a single drug, high IL-2 systemic toxicity, tumor microenvironment immunosuppression and the like in the existing PD-(L) 1 inhibitor, and provides technical support for detection, prevention and treatment of PD-L1 positive tumors.