43 results about "Protein folding" patented technology

The invention provides a plug-and-play Mi3 protein nanocage fusion protein with a VNP6 tag and a preparation method and application of the plug-and-play Mi3 protein nanocage fusion protein, the fusion protein comprises the VNP6 tag, a SpyCatch003 component, a Mi3 protein nanocage and a functional protein sequence, and the VNP6 tag is located at the N end of the fusion protein. The VNP6 peptide sequence or the variant thereof is utilized to induce a vesicle or vesicle-like structure beneficial to protein folding and stabilization in escherichia coli, so that the correct folding rate and activity of recombinant protein are improved while the overall intracellular molecular crowding effect is relieved. The core idea of the invention lies in that the internal structure of cells is regulated at low temperature, and the internal microenvironment of an escherichia coli expression system is optimized, so that protein molecules under high expression load can obtain more reasonable spatial distribution, and the problems of misfolding and aggregation caused by molecular crowding are reduced.

The invention provides a recombinant engineering bacterium for preparing recombinant equine albumin and application of the recombinant engineering bacterium, and relates to the technical field of genetic engineering. According to the invention, one or more of genes SED1 and TIP1 related to cell wall composition is / are knocked out in a targeted manner while the recombinant equine albumin is expressed, and / or one or more of genes PAC10 and YDJ1 related to protein folding promotion is / are overexpressed and integrated into a strain, so that the expression quantity of the recombinant equine albumin is improved. According to the recombinant engineering bacterium disclosed by the invention, the yield of the recombinant equine albumin can be obviously improved, the highest yield can reach 51.27 g / L, and compared with an unmodified recombinant engineering bacterium, the yield is improved by 5.38 times, and the recombinant engineering bacterium has a wide application prospect.

The invention relates to the field of preparation of materials for articular cartilage repair, in particular to collagen and chitosan cross-linked temperature-sensitive gel for articular cartilage repair and a preparation method of the collagen and chitosan cross-linked temperature-sensitive gel. The cartilage repair material prepared by the invention adopts the recombinant human collagen with a triple helix structure as a main raw material. The raw material is prepared by using a mammalian cell expression system, is close to protein folding and polymerization of natural protein, and has a spatial structure and modification necessary for active protein. The recombinant human collagen with the triple-helix structure is good in biocompatibility and free of rejection reaction and anaphylactic reaction, and the risk of disease transmission possibly caused by animal-derived collagen can be avoided. The injection type temperature-sensitive gel is liquid at low temperature and is converted into hydrogel at 37 DEG C, so that the injection type temperature-sensitive gel is suitable for being used as a transfer carrier for in-vivo injection treatment, secondary injury of an organism is effectively avoided, and the injection type temperature-sensitive gel has a wide clinical application prospect.

The present invention relates to the technical field of enzyme engineering. Disclosed are an artificial intelligence-based enzyme engineering method and system, a device, and a medium. The method comprises: on the basis of structural information of an engineered enzyme to be modified, using an inverse protein folding model to obtain a plurality of structurally compatible protein sequences on the basis of a given scaffold structure; on the basis of the plurality of structurally compatible protein sequences, obtaining a mutant amino acid frequency and a wild-type amino acid frequency at each sequence position; and on the basis of the mutant amino acid frequency and the wild-type amino acid frequency at each sequence position and the structural information of said engineered enzyme, as well as a first creation strategy, a second creation strategy, and a third creation strategy, obtaining a single-mutation variant set and a combinatorial-mutation variant set of said engineered enzyme. The present invention enables efficient and low-cost generation of single-mutation and combinatorial-mutation variant sets of an engineered enzyme to be modified, thereby achieving precise and efficient gene editing and effectively expanding the applicability and safety of gene editing.

The invention relates to a protein solubility prediction method and system based on GCN and an improved attention network. The method comprises the following steps: constructing a protein sequence data set; the method comprises the following steps: acquiring a protein three-dimensional structure file through AlphaFold3, and constructing a node feature vector; extracting position embedding, bidirectional projection direction features, a cross-node atom pair distance and a rotation relation, and constructing an edge feature vector; extracting global physicochemical property feature vectors of the protein; and constructing protein graph structure data, inputting the data to the graph convolutional network module and the improved graph attention network module, and performing training to obtain a graph convolutional network and an improved attention network model to perform protein solubility prediction. By extracting node and edge features and protein global physicochemical property features, subsequent model training is facilitated; and the two-way projection and the rotation relation enable the model to accurately sense the spatial orientation between residues, so that the model has more quantitative understanding on the protein folding and gathering driving force, and the accuracy of protein solubility prediction is improved.

A peptide which is characterized by: (a) dissolving 2 g or more at 20 DEG C in 100 mL of a 50 mM Tris hydrochloric acid buffer solution (pH 7.5) containing 0.3 M sodium chloride; (b) reversibly performing phase change in the Tris hydrochloric acid buffer solution, wherein the transformation temperature is 40-70 DEG C when 2g of the solution is dissolved in 100mL of the Tris hydrochloric acid buffer solution; and (c) when 2 g of the Tris hydrochloric acid buffer solution is dissolved in 100 mL of the Tris hydrochloric acid buffer solution, droplets are formed under the temperature condition above the transition temperature.

The invention provides a gene expression cassette for improving CsCE expression quantity and application. The gene expression cassette provided by the invention comprises a regulatory element and a target gene, the regulatory element comprises at least one of a coding sequence of dtRNA, a coding sequence of a signal peptide and a coding sequence of a fusion tag, and the target gene comprises a coding sequence of CsCE enzyme. Wherein the dtRNA contributes to keeping the structural stability when the CsCE enzyme is transcribed into mRNA, the signal peptide can promote the secretion of the CsCE enzyme, and the fusion tag can assist the correct folding of the CsCE enzyme, so that the expression of the CsCE enzyme can be synergistically regulated under the three-tube alignment of a DNA transcriptional mRNA layer, a protein secretion layer and a protein folding layer, the expression quantity of the CsCE enzyme can be effectively up-regulated, and the expression quantity of the CsCE enzyme can be effectively up-regulated. Therefore, the volume enzyme activity of the CsCE enzyme is improved, and the CsCE enzyme with higher volume enzyme activity can catalyze lactose to be converted into lactulose in the preparation of lactulose, so that the preparation yield of lactulose is improved.

The invention discloses application of HSF1A in preparation of a medicine for resisting lung cancer metastasis, and relates to the technical field of anti-tumor medicines. It is found for the first time that HSF1A can be used for inhibiting non-small cell lung cancer metastasis. The HSF1A is specifically combined with a CCT1 subunit ATPase structural domain of a TRIC / CCT compound, so that the protein folding function of the TRIC / CCT compound is interfered, and three key transfer promoting signal channels including YAP, STAT3 and mTOR are inhibited at the same time. In a pulmonary metastatic tumor model constructed by mouse tail intravenous injection, the formation of pulmonary metastatic tumor is obviously reduced by the HSF1A, and the fact that the HSF1A also has strong anti-metastatic capability in an in-vivo environment is proved; the safety is high, and the development and utilization prospects are good. The invention not only provides a new application of the HSF1A, but also provides a new thought and method for adjuvant therapy of cancers.

The invention belongs to the technical field of gene recombination, and particularly relates to a recombinant human III-type triple helix collagen, a recombinant yeast strain for expressing the recombinant human III-type triple helix collagen and a construction method of the recombinant human III-type triple helix collagen. The amino acid sequence of the recombinant human III-type triple-helix collagen is shown as SEQ ID NO. 1, and the recombinant human III-type triple-helix collagen has triple-helix conformation close to a natural biological structure of collagen and has good application value and potential. According to the recombinant yeast strain disclosed by the invention, human-derived III-type collagen and proline hydroxylase are co-expressed in yeast cells without YPS1 protease, and meanwhile, a gene beneficial to vesicle transport and protein folding is transferred, so that hydroxylation of the recombinant collagen can be realized, a natural triple helix conformation is formed, and the recombinant yeast strain can be used for preparing a recombinant collagen product. The degradation problem of the collagen in the expression process can be solved, and the extracellular secretion expression of the triple helix collagen is realized.

The invention aims to provide a method and device for constructing a codon sequence optimization model, a medium and a program product, and the method comprises the steps: constructing graph structure information corresponding to sample protein sequence information based on the sample protein sequence information and corresponding protein three-dimensional structure information, the graph structure information comprises node information matched with each amino acid and side information matched with each amino acid pair; inputting the graph structure information into a codon sequence optimization model of an encoder-decoder architecture to obtain a predicted codon sequence; and based on the predicted codon sequence and the codon sequence corresponding to the sample protein sequence information, combining a corresponding loss function to carry out model optimization, and obtaining a trained codon sequence optimization model. Through the three-dimensional structure of the protein, the model is helped to select codons in a more targeted manner, so that the codon sequence predicted by the model is closer to the actual protein folding process, and the translation speed of amino acid is matched with the folding speed.

The present invention discloses an injectable dual - biomimetic bone adhesive for promoting fracture healing and its preparation method, belonging to the field of biomaterial preparation. Inspired by the underwater adhesion mechanisms of marine mussels and barnacles, it uses biomimetic marine mussel substances (such as tannic acid), biomimetic marine barnacle substances (such as sodium alginate), silk fibroin, calcium chloride, and magnesium particles to form a dual - biomimetic bone adhesive with wet adhesion. Based on the hydrogen bonds, metal - phenol coordination bonds, electrostatic interactions, and β β - sheet protein folding conformations formed among the components, the obtained dual - biomimetic bone adhesive not only has good biocompatibility, excellent wet adhesion, and mechanical properties matching bone tissue strength, can be used for fracture bone fixation and repair, but also has the ability of in - situ gelation and can be directly injected at the injury site. The raw materials used in the adhesive prepared by the present invention are safe and widely sourced. Therefore, it is expected to achieve potential clinical application value in the fixation and repair of bone injuries.

The application discloses a fermentation method for improving structural stability and yield of recombinant human serum albumin, and belongs to the technical field of biological fermentation. 600 ≥180, and the living cell rate is greater than or equal to 90%; (2) during a methanol induction period, L-cysteine and L-methionine are added in batches in pulse mode with a mass ratio (0.5-2.0):1, and the final concentration is 0.1%-0.3%. The application promotes correct formation of disulfide bonds by optimizing seed quality and protein folding microenvironment. By using the method, the expression amount of rHSA reaches 24.3 g / L, the monomer purity is greater than or equal to 92%, the free sulfhydryl content is less than or equal to 3%, and the monomer purity reduction rate is less than or equal to 4% after 14 days of accelerated storage at 37 DEG C. The application significantly improves product stability while maintaining high yield, and provides an innovative process for industrialized production of high-quality rHSA.

The application discloses a yeast strain with high yield of cannabinoid synthesis precursors, a construction method and application thereof, and belongs to the technical field of synthetic biology and microorganisms. The application takes Saccharomyces cerevisiae as a host, screens genes participating in protein folding proteins to obtain an engineering strain for improving the yield of OA / OLO, further down-regulates the expression of FAS1 and MvaE enzymes, and then inserts a gene expression cassette CsAAE1-TKS-OA cassette into the rDNA site of the Saccharomyces cerevisiae genome in multiple copies to obtain a genetic engineering strain with improved OA / OLO yield. The application further improves the yield of OA / OLO by optimizing the substrate in the fermentation system, i.e. using a mixed substrate of sodium caproate and ethyl caproate, and the yield of OA / OLO in a 10L fermenter is about 10 mM OA and 10 mM OLO, and the equivalent yield is 2.2 g / L and 1.8 g / L respectively.

This invention relates to a detection kit and preparation method for enhancing the detection efficacy of autoimmune encephalitis (CBA) antibodies. The kit comprises genetically engineered 293T cells stably integrating and co-expressing the eIF2α S52A mutant and HSP70, and transiently transfected with CBA-associated antigens. The preparation method includes constructing a co-expression vector, establishing a stable transfection cell line, stress preconditioning treatment, antigen transfection, and kit assembly. A method for assessing antibody affinity maturation using this kit is also provided. By synergistically modifying detection cells at three levels—translational regulation, protein folding, and anti-apoptosis—the invention significantly increases antigen expression, reduces apoptosis, and improves detection sensitivity and specificity. Furthermore, it integrates antibody affinity assessment into CBA detection for the first time, providing auxiliary information for clinical staging.

The invention relates to an extraction method of a bioactive composite peptide and application of the bioactive composite peptide in cosmetics. The composite peptide comprises peptide fragments with 20 specific amino acid sequences and precursor proteins derived from 12 genes, the total relative content is 63.82%, and the collagen related sequence accounts for 22%. A papain digestion combined ultrafiltration purification technology is adopted for extraction, the molecular weight is smaller than 2 kDa, and skin and hair barriers can be conveniently penetrated. The peptide fragments synergistically promote fibroblast activity, extracellular matrix construction and protein folding, are suitable for skin care and hair care products, and realize anti-aging, repair and damaged hair quality improvement. The scheme provided by the invention is clear in component, efficient in extraction and relatively low in cost.

The invention provides a recombinant engineering bacterium for preparing recombinant canine albumin and application of the recombinant engineering bacterium, and relates to the field of biochemistry, in particular to the technical field of genetic engineering. One or more genes of PBN1, KAR2 and ERV2 related to protein folding are overexpressed and integrated into the strain while the recombinant canine albumin is expressed, so that the expression of the canine albumin is remarkably improved, the relative protein expression quantity can be up to 491% at most, the specific yield can be up to 32.83 g / L at most, and the recombinant canine albumin has a wide application prospect.

An apparatus, system, and method for studying protein folding in the native cellular environment is provided. The invention, termed pcIC-FPOP, combines pulse-chase experiments with in-cell protein footprinting coupled to mass spectrometry. This enables very high resolution information on the folding or mis-folding of proteins. The system (100) includes a multi-well plate (110), an incubator (120), a stage (130), a subsystem of reservoirs (172) and pumps (174), a laser source (140) and beam steering optics (150), and a computer system (160) programmed with a control module (162) to control the operation of the laser (140), optics (150), incubator (120), stage (130), or pumps (174), or some combination. This method permits studies that fill gaps in knowledge on protein folding and its role in disease.

The invention discloses construction and application of an engineering strain capable of normally growing at 35 DEG C and realizing high yield of xanthan gum. The method comprises the following steps: by taking xanthomonas campestris XC1 as an initial strain, carrying out ARTP mutagenesis treatment, and screening a mutant strain which can normally grow under the condition of 35 DEG C; the mutant strain is subjected to multiple rounds of superposition transformation, and multiple physiological restrictions under high temperature stress are systematically broken by sequentially strengthening a protein folding system (grpE-ATGA-dnaK), activating outer membrane stress regulation (rpoE), constructing an anti-oxidation barrier (katB) and strengthening a cell membrane structure (polCDE); the finally obtained engineering strain shows the performance far better than that of an initial strain under the condition of 35 DEG C; the biomass of the strain is increased by 207.7% compared with that of an initial strain XC1, and the yield of xanthan gum is increased by 75.5% and reaches 25.8 g / L, which is consistent with the yield of xanthan gum under the fermentation condition of 28 DEG C.

Provided is a protein folding agent containing a compound (A) represented by general formula (A). In general formula (A), R1 to R6 are each independently a C1-24 aliphatic hydrocarbon group. Y1and Y2each independently represent a C1-6 aliphatic hydrocarbon group. Moreover, n is an integer of 1 or greater, and Xn- is an n-valent anion. Also provided is a protein folding composition containing the compound (A) and a protein aggregation inhibitor. Furthermore, also provided is a protein folding method including a step (a) for incubating a protein in the presence of the protein folding agent.

The invention provides a gene expression cassette for improving CsCE expression quantity and application. The gene expression cassette provided by the invention comprises a regulatory element and a target gene, the regulatory element comprises a coding sequence of a fusion tag, and the target gene comprises a coding sequence of CsCE enzyme. The fusion tag can promote the expression quantity of the CsCE enzyme on the level of regulating and controlling protein folding, and the expression quantity of the CsCE enzyme is improved through the synergistic effect of the fusion tag and the CsCE enzyme, so that the volume enzyme activity of the CsCE enzyme is improved, the CsCE enzyme with higher volume enzyme activity can catalyze lactose to be converted into lactulose in the preparation of lactulose, and the lactulose can be used for preparing lactulose. Further, the preparation yield of the lactulose is improved.

It forms an object of the present invention a method for determining the folding trajectory of a given protein comprising: - generating a starting configuration; - defining a metric to evaluate the distance between configurations; - generating an array of protein configurations constituting the trajectory. It forms a further object a method for identifying a target configuration suitable for being tested as target for drug discovery procedures.

The invention provides a recombinant engineering bacterium for preparing recombinant bovine albumin and application of the recombinant engineering bacterium, and relates to the technical field of genetic engineering. When the recombinant bovine albumin is expressed, one or more of protein degrading enzyme genes MKC7 and ULP1 are knocked out in a targeted manner, and / or one or more of protein folding related genes PDI-2 and SHR3 are overexpressed and integrated into the strain, so that the expression quantity of the recombinant bovine albumin is increased. According to the recombinant engineering bacterium disclosed by the invention, the yield of the recombinant bovine albumin can be obviously improved, the highest yield can reach 38.79 g / L, and compared with an unmodified recombinant engineering bacterium, the yield is improved by 4.85 times, and the recombinant engineering bacterium has a wide application prospect.

The invention discloses a preparation method of an HIV (Human Immunodeficiency Virus) envelope protein gp160. The preparation method comprises an effective interception and selection mode of amino acid sequences of envelope proteins gp160-I and gp160-II of HIV-I and HIV-II, an optimized nucleotide sequence, an expression plasmid construction method and a purification and preservation method. The gp160-I protein and the gp160-II protein are expressed through mammalian cells, the protein expression efficiency and the protein folding modification accuracy are greatly improved by adding the artificial signal peptide and the JSD promoter, and the gp160-I protein and the gp160-II protein have high biological activity and thermal stability and have the advantages that fermentation is easy to amplify, separation and purification are easy, and the coating use amount is low.

The invention discloses application of brazilin in preparation of a medicine for inducing endoplasmic reticulum stress of bladder cancer cells. Experiments provided by the invention prove that brazilin can inhibit the progress of bladder cancer in vitro and in vivo, and reduce the Khib level of protein enriched in a protein folding pathway, so that endoplasmic reticulum stress is triggered, a PERK-eIF2alpha-ATF4-CHOP axis is activated, and CHOP-mediated cell apoptosis is driven. According to the application disclosed by the invention, the anti-tumor effect of the brazilin is researched by associating with Khib proteome remodeling and endoplasmic reticulum stress-induced apoptosis for the first time, and the research shows that the brazilin can be used for preparing medicines for treating bladder cancer or assisting in postoperative treatment.

The invention discloses an optical fiber mechanical resonance probe sensor and a protein folding process monitoring method. In the sensor, a laser sends a laser signal to an optical fiber grating through a circulator; the driving device drives the fiber bragg grating and the vibration part to synchronously do subharmonic vibration, the grating period of the fiber bragg grating changes periodically in the vibration process, the reflection spectrum of the fiber bragg grating shifts periodically, and after the fiber bragg grating receives the laser signal, the vibration part vibrates; the intensity of the reflected light reversely transmitted to the photoelectric detector through the circulator also changes periodically; the characteristic parameters of the to-be-detected substance inserted into the vibration part are different, and the periodic change degrees of the reflected light intensity are different; the photoelectric detector converts the reflected light into an electric signal, and the analysis device determines the characteristic parameters of the to-be-detected substance according to the intensity change degree of the electric signal. According to the method, accurate and high-sensitivity measurement of characteristic parameters can be realized, fluorophore does not need to be introduced in the protein folding process, and accurate and high-sensitivity artifact-free characterization can be realized.

A protein folding agent which contains at least one compound selected from the group consisting of (A) to (B): (A) a cyclic polyamine that contains one or more thiol groups or disulfide bonds and is capable of bonding to transition metal ions; (B) a compound in which two or more cyclic polyamines (A) are bonded to each other via disulfide bonds between the thiol groups; (C) a complex of the cyclic polyamine of (A) or the compound of (B) with a transition metal ion; (D) a salt of the cyclic polyamine of (A) or the compound of (B); and (E) a solvate of the cyclic polyamine of (A) or the compound of (B).

It is an object of the present invention to provide a method for determining a folding trajectory of a given protein comprising: - generating a starting conformation; - defining a metric for assessing the distance between conformations; - generating an array of protein conformations constituting a trajectory. It is another object of the present invention to provide a method for identifying target conformations suitable for testing as targets of a drug discovery program.

The invention discloses a prediction method of a protein multi-conformation structure and electronic equipment thereof. Many proteins have a plurality of local optimal conformations, and MSA information is an important basis for protein structure prediction of AlphaFold2. However, MSA information which is usually obtained through sequence search and is composed of natural sequences can only guide a model to predict a local optimal conformation, and it is difficult to effectively explore a plurality of local optimal conformations possibly corresponding to a single sequence. According to the method, a larger conformational space is explored in a mode of manually and randomly generating initial MSA information, and the possibility of finding multiple protein folding forms corresponding to a single sequence is improved. Meanwhile, self consistency and physical rationality of the structure are evaluated and predicted in a multi-dimensional mode, MSA information is directly optimized on the global energy landscape, and the exploration efficiency of the multi-conformation structure is improved.

The invention discloses a method for optimizing the overall length of an expression sequence of chondroitin sulfotransferase UST in pichia pastoris, and belongs to the technical field of biological engineering. According to the invention, UST is modified and optimized by using a synthetic biological means, so that the breakage of UST in the expression process is reduced, and the enzyme activity is improved. The method specifically comprises the following steps: (1) truncating UST; (2) co-expressing a dissolution-promoting tag to promote folding and translation of protein; (3) on the basis of the rational design of the protein sequence, replacing the Linker to reduce the fracture at the connecting peptide; and (4) transforming the protease cleavage site of the UST. Through the strategies, breakage of the enzyme in the expression process is remarkably reduced, the technical problem that exogenous expression of the wild enzyme is difficult is solved, and compared with the enzymatic activity of a truncated mutant, the enzymatic activity is improved by 10.7 times, so that the industrial process of preparing chondroitin sulfate D (CSD) from the biological enzyme is accelerated.