81results about "Fusions for enhanced expression stability/folding" patented technology

The invention discloses a method for improving the solubility and thermal stability of sweet protein, and belongs to the technical field of biosynthesis, the method comprises the following steps: constructing a gene tandem recombinant plasmid containing a monellin x-3C-sfGFP-3C-monellin y expression cassette, x is greater than or equal to 1, y is greater than or equal to 1, 5 is greater than or equal to x + y is greater than or equal to 3, a 3C protease recognition sequence is also inserted between adjacent copies of monellin, and each monellin is connected with a purification tag; the gene tandem recombinant plasmid is transformed into escherichia coli and inducible expression is carried out, thalli are split and purified to obtain fusion protein, 3C protease is used for enzyme digestion, and the target protein is obtained after re-purification. The total protein yield and the solubility proportion are remarkably improved by adopting a series construction mode of plasmids, meanwhile, the stability of monellin is effectively improved, the purification step is simpler and more convenient, and the method is suitable for industrial production.

Provided are a method for constructing a soluble expression plasmid mutant library, and the use thereof. The method for constructing the soluble expression plasmid mutant library comprises: introducing mutations into a ribosome binding site on a soluble expression plasmid, a sequence composition and length of a region between the ribosome binding site and an initiation codon of a fusion protein to be expressed, and a translation initiation region, so as to obtain a mutant library. By means of the method, plasmid mutants with increased expression levels are obtained, thereby increasing the expression level of a target fusion protein and the final yield of a target polypeptide. The present invention solves the problem of low soluble expression levels of certain polypeptides in Escherichia coli.

The present invention relates to research tools for structural biology, particularly for facilitating the determination of three-dimensional structures of biological macromolecules. More specifically, the present invention helps to improve the overall feasibility of structure determination, resulting in higher resolution and better quality of three-dimensional structures of proteins through complex formation with novel fusion polypeptides.

The present disclosure relates generally to recombinant polynucleotides comprising novel pro-region DNA sequences. Certain aspects of the disclosure relate to recombinant Gram-positive bacterial strains comprising one or more introduced polynucleotides comprising novel pro-region DNA sequences operably linked to a DNA sequence encoding a protein of interest.

Provided herein are compositions and methods for adoptive cell therapy comprising engineered immune cells that express a tumor antigen-targeted chimeric antigen receptor and a prodrug converting enzyme.

The invention relates to the technical field of biology, in particular to a recombinant pichia pastoris engineering bacterium, a construction method of the recombinant pichia pastoris engineering bacterium and application of the recombinant pichia pastoris engineering bacterium in secretory expression of ovotransferrin. The heterologous expression of ovotransferrin is effectively realized by optimizing ovotransferrin genes and utilizing molecular chaperone genes to strengthen the regulation and control capability of hosts, and meanwhile, by optimizing signal peptides and constructing high-copy recombinant pichia pastoris expression strains, the low-copy expression condition is verified and compared by utilizing fermentation expression, so that the heterologous expression of ovotransferrin is realized. According to the high-copy recombinant pichia pastoris engineering bacteria constructed by the invention, the ovotransferrin expression quantity is obviously improved and reaches 140 mg / L, the secretory expression efficiency of the ovotransferrin is effectively improved, and theoretical guidance is provided for heterologous expression and industrial production of the ovotransferrin.

The present disclosure provides a peptide tag, and a nucleic acid encoding the peptide tag. The peptide tag of the present disclosure can reduce an aggregation property of a protein in a cell. Specifically, the peptide tag of the present disclosure can be a peptide tag in which 5% or more and less than 45% of amino acids contained in an amino acid sequence thereof are acidic amino acids, and (b) 20% or more of the amino acids contained in the amino acid sequence are amino acids selected from the group consisting of F, P, Y, G, S, Q, N, and A.

The invention relates to construction of a proline hydroxylase alpha subunit mutant from a human placenta and an expression vector of the proline hydroxylase alpha subunit mutant, and a mutant protein which is efficiently expressed in Ecoli BL21 (DE3) and has greatly improved hydroxylation efficiency and a construction body of the mutant protein are obtained by analyzing and screening a natural hydroxylase subunit.

Disclosed herein are rare earth element (REE) sensors comprising an REE binding element and a fluorescent component, which can be expressed on a cell surface. Also disclosed are systems and methods of recovering rare earth elements from a sample, the method comprising exposing an aqueous solution comprising one or more rare earth elements. Also disclosed are methods of discovering new, useful REE binding elements.

This invention belongs to the field of biomedicine and relates to the DHX8 fusion protein and its preparation method. The amino acid sequence of the DHX8 fusion protein is shown in SEQ ID NO:1. The method of this invention includes: 1) amplifying the nucleic acid sequence encoding the DHX8 fusion protein; 2) cloning the nucleic acid sequence into a prokaryotic expression vector; 3) transforming the prokaryotic expression vector into E. coli strain; 4) inducing the expression of the DHX8 fusion protein; and 5) purifying the DHX8 fusion protein. The DHX8 fusion protein of this invention has ATP hydrolase activity and helicase activity. The method of this invention is easy to mass-produce and can be used for high-throughput screening of DHX8 helicase inhibitors. Furthermore, its expression system is simple.

The present invention relates to coronavirus antigens comprising a coronavirus nucleocapsid specific amino acid sequence, compositions and kits comprising them and methods of production thereof. Further included are methods of using said coronavirus antigens for detecting anti-coronavirus antibodies in a sample, and methods of differentiating between immune responses in a patient caused by a natural coronavirus infection or by vaccination against coronavirus.

The invention belongs to the technical field of globular protein synthesis, and particularly relates to a chaperonin-assisted recombinant human hFGF-2 protein preparation method and application thereof, the chaperonin-assisted recombinant human hFGF-2 protein preparation method comprises the following steps: S1, constructing a recombinant vector TrxA-6H-DDDDK-hFGF2 containing an hFGF-2 fusion protein coding sequence; s2, transforming the recombinant vector into an escherichia coli host cell for induced expression to obtain an expression thallus; s3, crushing the expression thalli to obtain a cell lysis supernatant; s4, taking the supernate, carrying out nickel column affinity chromatography, carrying out desalination treatment on the fusion protein by adopting gel chromatography, and collecting a fusion protein eluent; s5, performing enterokinase cutting treatment on the fusion protein to obtain an enzyme-digested product; s6, performing heparin affinity chromatography on the enzyme digestion product, and collecting hFGF-2 protein eluent; and S7, carrying out dialysis treatment on the protein eluent to obtain the recombinant hFGF-2 protein.

Disclosed are a thioredoxin mutant, preparation method thereof, and application thereof in production of recombinant fusion protein. The thioredoxin mutant is prepared by modifying at least one amino acid in the amino acid sequence of SEQ ID NO: 1.

The invention relates to the technical field of biological medicines, and discloses a dual-targeting adhesion-immune activation fusion peptide, an anti-escherichia coli O157: H7 monoclonal antibody GS2-D3, curcumin nanoparticles and a probiotic composition composed of the curcumin nanoparticles. The fusion peptide solves structural conflicts by inserting an alpha helix stable domain composed of four EAAAK repetitive units and a GPGP flexible buffer domain, a targeting domain YIGSR and an MUC2 binding domain PTPSFTT are introduced to improve the targeting efficiency, and the enzymolysis resistance is enhanced through site mutation; the monoclonal antibody GS2-D3 can be used for specifically recognizing escherichia coli O157: H7; the curcumin nanoparticles improve the stability and bioavailability of curcumin. The probiotic composition contains the components, has the effects of efficient colonization, bacteriostasis, inflammation resistance and intestinal flora regulation, can effectively treat intestinal inflammation, is low in cost and high in safety, and has good clinical transformation potential.

This disclosure generally relates to fusion proteins comprising TAL Arrays targeting a repetitive element and a transposase domain comprising amino terminal deletions, as well as dual cysteine rich domains (CRD), for targeting site-specific transposition into ribosomal DNA (rDNA) repeats or LINE1 repetitive elements, polynucleotides and vectors encoding the fusion proteins, and methods of use therefor.

The present invention relates to a protein and a vaccine against infections by a SARS-CoV-2 Omicron variant XBB and subvariants thereof, which belongs to the medicine field. To address the lack of effective prophylactic and therapeutic agents against the infections caused by SARS-CoV-2 Omicron variant XBB and subvariants thereof, the present invention provides proteins and vaccines against infections by the variants, the vaccines are designed based on the full-length S protein, the receptor-binding domain (RBD) sequence and optimized sequences of SARS-CoV-2 Omicron variant XBB and subvariant XBB.1.5, thereof, which are are capable of aiding the host in combating coronavirus infections, and particularly have a relatively good preventive and therapeutic effect against cross-infections caused by SARS-CoV-2 Omicron variant XBB and subvariants thereof.

The present invention relates to a corona antigen comprising a corona nucleocapsid-specific amino acid sequence, a composition and a reagent kit comprising the same, and a method for producing the same. It also includes a method for detecting anti-corona antibodies in a sample using the corona antigen, and a method for differential diagnosis of a patient's immune response due to natural corona infection or vaccination against corona.

Variants of the ZF5.3 peptide having Cys substitutions of one or both His residues of the Cys2His2 Zn(II) coordination site, to form Cys3His (CCHC) or Cys4 (AV5.3), respectively, are used in fusions of the peptides with cargo domains, delivery vehicles and delivery methods.

The present invention provides compositions and methods comprising an activator of interleukin-18 (IL-18) activity for use in therapeutic and non-therapeutic applications. The activator provides IL-18 signaling activity even in the presence of an inhibitory molecule 5 such as IL-18 binding protein (IL-18BP).

The invention discloses a recombinant Pasteurella multocida-sourced uridine diphosphate glucuronide transferase (PmHS2) mutant and a preparation method thereof, and relates to the technical field of biology, the mutant is obtained by cloning a coding gene to a pET26b (+) vector, transforming BL21 (DE3) Escherichia coli competent cells, and then transforming the recombinant Pasteurella multocida-sourced uridine diphosphate glucuronide transferase (PmHS2) to a pET26b (+) vector. And carrying out IPTG (isopropyl-beta-d-thiogalactoside) induced culture, ultrasonication and nickel affinity chromatography purification to obtain high-purity protein. Compared with wild type recombinant PmHS2, the activity of N-acetyl glucosamino transferase of the mutant is improved by 70%, the residual activity is 67.1% after the mutant is stored at room temperature for 5 days, the soluble expression quantity is improved by 6 times, and the mutant and the preparation method have the advantages of high catalytic efficiency, high stability and high solubility, and the mutant and the preparation method are mature in process, controllable in cost and suitable for industrial production. The method can be efficiently used in the fields of heparin and derivative synthesis, traditional Chinese medicine active ingredient glycosylation and the like, is suitable for large-scale production and has a wide application prospect.

The invention relates to a recombinant protein aiming at KRAS G12D mutation and application of the recombinant protein. In particular, the recombinant protein comprises an immunostimulatory domain, and an antigen domain comprising at least one KRAS G12D antigen fragment.

The present invention relates to methods and transformed host cells for the production of eriodictyol from naringenin via bioconversion.

Disclosed are fusion polypeptides that are substrates for white Kunitz's transglutaminase. The fusion polypeptides comprise one or more FKBP chaperone proteins and a target polypeptide. Each of these elements is separated from adjacent elements by a linker amino acid sequence. It has been found that it is advantageous to insert a glutamic acid-containing transglutaminase recognition motif into the linker amino acid chain. The subsequent labeling reaction catalyzed by the transglutaminase surprisingly provides a labeled fusion polypeptide with superior properties compared to chemically randomly labeled fusion polypeptides of similar design. Assays and kits for detecting a target antibody in a sample in vitro are provided.

The invention relates to hyperbaric devices for inactivating microorganisms and viruses while retaining their immunogenicity and for making and producing the soluble, disaggregated, refolded or active immunogenic or therapeutic proteins from inclusion bodies produced from prokaryotes or eukaryotes. The invention encompasses hyperbaric methods for inactivating pathogenic organisms, and methods for producing vaccine compositions using the inactivated pathogens. The hyperbarically inactivated microorganisms are safer and more immunogenic than chemically inactivated microorganisms. Similarly, the solubilized proteins have superior properties compared to more heavily aggregated proteins, including reduced non-specific immune reactions.

Disclosed herein is a recombinant terminal deoxynucleotidyl transferase (TdT). In some embodiments, the recombinant TdT comprises an amino acid sequence at least 80% identical to bovine TdT, wherein the recombinant TdT comprises one or more amino acid substitution mutations at one or more positions functionally equivalent to Glu191, Lys193, Glu194, Asp242, Lys287, Phe296, Met299, Thr342, and His421 of bovine TdT.

The object of the present invention is to provide novel means that can be used for solubilizing proteins with poor water solubility. Provided is a hydrophilic solubilizing group for proteins or peptides, comprising a sugar chain moiety; and a functional group moiety that is bound to the amino or carboxy group of said sugar chain, and that binds to the amino acid side chain and can be detached from said protein or amino acid side chain in the presence of an acid.

The present disclosure provides compositions and methods relating to modified mini-nucleosome core proteins and / or delivery of nucleic acids. In particular, the present disclosure includes, among other things, non-viral proteinaceous vehicles for delivery of nucleic acids. In various embodiments, non-viral proteinaceous vehicles provided herein include (a) a nucleic acid binding domain; (b) a targeting domain; (c) a nucleic acid release domain; and, optionally. (d) further domains including, e.g., one or more of a stability domain, an oligomerization domain, and / or a linker domain. In various embodiments, the proteinaceous vehicles include one or more modified residues.

The invention discloses a method for preparing a collagen heterotrimer by an intracellular one-step method, and belongs to the technical field of genetic engineering. According to the method, three collagen heterotrimer single chains are constructed in a plasmid vector for co-expression, the sequence of the heterotrimer single chains is changed by inserting a tag, and the collagen heterotrimer is efficiently synthesized in cells by a one-step method by using recombinant bacteria for expression and purification. According to the method disclosed by the invention, one-step preparation of the heterotrimer collagen with different A, B and C chains, which is high in thermal stability and relatively high in yield, is realized; on the basis of the method disclosed by the invention, the heterotrimer collagen composed of any collagen fragment can be theoretically prepared, and the heterotrimer collagen comprises type I collagen; on the basis, according to the collagen prepared by an intracellular one-step method, the Tm value of a heterotrimer prepared by intracellular folding is 42 DEG C, and the heat stability is relatively high; and the intracellular folded collagen heterotrimer structure is obviously superior to in-vitro folded collagen heterotrimer structure.

The invention relates to a recombinant chondroitin-6-O-sulfotransferase mutant and application of the recombinant chondroitin-6-O-sulfotransferase mutant in synthesis of chondroitin sulfate C, and belongs to the technical field of bioengineering. According to the invention, a dissolution promoting label is fused at the N end of a chondroitin-6-O-sulfotransferase mutant, so that the efficient soluble expression of the enzyme is successfully realized, and the proportion of soluble components is as high as 90%. The mutant HsC6ST-delta loop has the advantages that by carrying out amino acid sequence truncation on chondroitin-6-O-sulfotransferase, the constructed mutant HsC6ST-delta loop has higher chondroitin-6-O-sulfonation activity compared with HsC6ST chondroitin-6-O-sulfonation, the sulfonation rate reaches 78.4% after reaction is carried out for 12 h under the conditions that the temperature is 40 DEG C and the pH is 8.0, and the Tm and half-life period are increased by 9 DEG C and 1.54 h compared with those of an original enzyme.

The invention discloses a protein for enhancing foreign protein expression and application thereof. The target protein-OMP43 recombinant protein can be obtained by fusing and connecting the protein OMP43 to the C end of the target protein, so that the expression level of the target protein in a heterologous expression system is improved. The recombinant protein En6-OMP43 is constructed and obtained by taking bacteriophage lyase En6 as an example. Experimental results show that after the OMP43 is fused, the antibacterial activity of the recombinant protein lyase on acinetobacter baumannii is maintained. The protein OMP43 serving as an expression enhancing element is high in universality, simple and convenient to construct and suitable for being modularly applied to foreign protein expression and preparation.