12381results about "Peptide preparation methods" patented technology

The invention relates to the field of biological medicine, in particular to a stapled peptide targeting RAS-Raf protein interaction and application of the stapled peptide, the stapled peptide is obtained in the mode that Ac-SLHDCLMKALKVR-NH2 and Ac-SLHDCLMKALKVRGL-NH2 serve as peptide chain templates, amino acid at the i site and amino acid at the (i + 4) site are replaced with S5 and cyclized, and the nitrogen terminal is further modified with stearic acid. The stapled peptide can effectively inhibit proliferation and migration of tumor cells; the serum stability is high, and meanwhile, the cell transmembrane capability is excellent, so that target protein in cells can be better targeted, and the biological function of the target protein can be exerted. Therefore, the alphaH helical conformation of the RBD of the RAF can be stabilized through the stapled peptide and a nitrogen-terminal fatty acid modification strategy, the membrane permeability and stability of the RAF are improved, the binding force of the RAF and RAS is further improved, and proliferation and migration of various tumor cells are inhibited.

A recombinant humanized collagen and a preparation method therefor. The recombinant humanized type III collagen can be efficiently and stably expressed in three expression systems of yeast, Escherichia coli, and CHO cells, and has the biological activity superior to that of a commercially available collagen product. The recombinant humanized type III collagen has structural characteristics and functional activity similar to those of a natural collagen, and thus has wide application prospects in biomedical materials, tissue engineering products, cosmetics, foods, health care products or drugs, medical instruments, medical cosmetology and the like.

The invention relates to the field of preparation and application of biological peptides, in particular to a hippocampal swelling peptide and application thereof in preparation of functional products for repairing male reproductive system injury. A green controllable enzymolysis technology is utilized to obtain protein polypeptide with nutritional, health-care and medicinal values, five active peptide sequences with high biological activity are obtained through further research on the basis, the high-purity active peptide is obtained through a chemical synthesis mode, and the biological activity of the peptide is verified through mouse spermatogonium.

The invention discloses a bovine serum albumin combined nano antibody and a preparation method and application thereof, the amino acid sequence of the bovine serum albumin combined nano antibody Nb1 is shown as SEQ.ID No.1, the nano antibody Nb not only has high affinity to bovine serum albumin, but also has good binding activity to both human serum albumin and mouse serum albumin, and the nano antibody Nb has high affinity to human serum albumin and mouse serum albumin. And the antibody has a relatively good broad-spectrum application range, and can be widely applied to the aspects of drug half-life period enhancement, tumor targeted therapy and imaging, immunodetection or diagnosis, recombinant albumin purification or enrichment and the like.

The invention discloses a preparation method of yak bone collagen peptide for increasing bone mineral density and the yak bone collagen peptide. The invention provides a preparation method of yak bone collagen peptide for increasing bone mineral density. The preparation method comprises the following steps: providing yak bone powder; mixing the yak bone meal with a phosphate buffer solution, adjusting the pH value to 5-5.5, mixing with compound bacteria, and carrying out demineralization treatment to obtain a demineralized product; mixing the demineralized product with a compound enzyme, and carrying out an enzymolysis reaction to obtain an enzymolysis product; heating, centrifugally filtering and freeze-drying the enzymolysis product to prepare yak bone collagen peptide; wherein the compound enzyme comprises trypsin, alkaline protease and flavourzyme, and the compound bacteria comprise lactobacillus plantarum and propionibacterium. Lactobacillus plantarum and propionibacterium in the compound bacteria are subjected to synergistic fermentation, and are combined with the enzymolysis reaction of the compound enzyme, so that collagen is decomposed into small molecule peptides more efficiently, the extraction rate of bone collagen peptide is increased, and the bone mineral density is increased.

The invention discloses two brand-new bioactive peptides with antioxidant and alpha-glucosidase inhibitory activity in traditional Chinese medicine hippocampus. The sequences of the novel bioactive peptides provided by the invention are respectively YLPPNW and SVWLGGSLL. According to the method, purity and structure identification is carried out on the new bioactive peptide obtained through separation by adopting liquid phase, primary mass spectrum and secondary mass spectrum, and a material basis is provided for further quality control and drug effect research of the traditional Chinese medicine hippocampus.

The invention discloses a xanthine oxidase inhibitory peptide with uric acid reducing activity and application thereof, and belongs to the technical field of biological medicines.The xanthine oxidase inhibitory peptide is obtained by conducting enzymolysis, separation and purification on processing byproducts such as litopenaeus vannamei heads and shells with xanthine oxidase inhibitory activity. The xanthine oxidase inhibitory peptide is screened by using a molecular docking technology, and the amino acid sequence of the xanthine oxidase inhibitory peptide is Pro-Pro-Val-Pro-Pro-Pro. The xanthine oxidase inhibitory peptide has an XOD (X-Oxidase) half inhibitory concentration of 3.181 + / -0.1786 mM. The invention further proves that the xanthine oxidase inhibitory peptide has a certain improvement effect on hyperuricemia mice, and the xanthine oxidase inhibitory peptide mainly has the effects of reducing the content of serum uric acid, creatinine and urea nitrogen of the hyperuricemia mice, inhibiting the activity of xanthine oxidase (XOD) in serum and liver of the mice, inhibiting synthesis of uric acid and improving kidney injury of the mice, and the xanthine oxidase inhibitory peptide has a certain improvement effect on the hyperuricemia mice through Toxinpred prediction. The xanthine oxidase inhibitory peptide uric acid reducing peptide is free of toxic and side effects and has a wide market application prospect.

This disclosure relates to dimeric immunotherapeutics that comprise two IgGs that are crosslinked with a disulfide bond. The two IgGs may be chimeras of two different heavy chains, in which one heavy chain includes a cysteine mutation that forms the disulfide bond, and the other heavy chain lacks the cysteine mutation. The presence of a cysteine mutation in only one of the heavy chains of an IgG avoids two disulfide bonds between the two IgGs, which increases the accessible orientations between the two crosslinked IgGs, and also avoids the formation of trimers and higher-order oligomers.

The invention relates to the technical field of hippocampus extract, in particular to a hippocampus-sourced neuroprotection and anti-oxidative stress polypeptide and a preparation method thereof.The amino acid sequence of the polypeptide is shown as SEQ ID No.1. The preparation method comprises the following steps that 1, 500 g of fresh hippocampus is weighed, surface silt is removed, freeze-drying is conducted at the temperature of-60 DEG C, then the hippocampus is smashed through a smashing machine and sieved through a 20-mesh sieve, and the hippocampus extract is obtained; dialyzing with distilled water for 24 hours, and freeze-drying to obtain hippocampus powder; (2) weighing 200g of hippocampus powder, adding 1000ml of 95% ethanol, extracting for three times, removing fat-soluble substances, and extracting and freeze-drying precipitates by using a 1 mol / L NaCl solution under the condition of 4 DEG C in combination with ultrasonic assistance to obtain crude hippocampus protein; (3) the hippocampus crude protein is taken, the hippocampus polypeptide is prepared through an ultrasonic-assisted bionic digestion method, and the hippocampus polypeptide has the advantages of being specific in molecular structure, clear in action mechanism, stable in gastrointestinal tracts, capable of protecting nerves, resistant to oxidative stress and the like.

The invention relates to a recombinant A type humanized XVII type collagen as well as construction and application thereof, the protein is the humanized XVII type collagen which is composed of an intracellular region, a transmembrane region and an extracellular region, and the amino acid sequence is as shown in SEQ No. 1. The hair follicle repairing agent has the advantages of hair follicle repairing, hair regeneration, good biological activities of cell proliferation, cell adhesion and the like, and can be widely applied to the fields of medicines, medical instruments, biological materials, tissue engineering, cosmetics and the like. The gene sequence of the recombinant A type XVII collagen is 100% identical to the corresponding part of the gene sequence of the recombinant A type XVII collagen, so that the recombinant A type XVII collagen has good hydrophilicity and high activity, and has application potential in the fields of biomedical materials, beauty cosmetics, skin care products and the like.

This disclosure relates to dimeric immunotherapeutics that comprise two IgGs that are crosslinked with a disulfide bond. The two IgGs may be chimeras of two different heavy chains, in which one heavy chain includes a cysteine mutation that forms the disulfide bond, and the other heavy chain lacks the cysteine mutation. The presence of a cysteine mutation in only one of the heavy chains of an IgG avoids two disulfide bonds between the two IgGs, which increases the accessible orientations between the two crosslinked IgGs, and also avoids the formation of trimers and higher-order oligomers.

The invention discloses a BamA-targeting antibacterial peptide as well as a preparation method and application thereof, and is characterized in that amino acids in a sequence are all D-type amino acids, and the amino acid sequence is as follows: w-r-r-w-r-r-p-w-k-r (dTrp-dArg-dArg-dTrp-dArg-dArg-dPro-dTrp-dLys-dArg). The antibacterial peptide provided by the invention has good antibacterial activity, can be synthesized by adopting an Fmoc solid-phase chemical method, is low in preparation difficulty, and has high affinity with target protein BamA.

The invention relates to the technical field of protein purification, in particular to a biological method for purifying fusion protein through two different affinity tags. Two affinity purification tags and a dissolution promoting tag are perfectly combined, so that soluble expression of recombinant protein is ensured, high-purity target protein can be obtained through a two-step mild and efficient affinity purification process, the function and activity of the protein are ensured, a complex'capture-medium purification-fine purification 'multi-step purification process is avoided, and the method is suitable for industrial production. The purification process is shortened, the purification time is shortened, the purification efficiency is improved, and the method can be used for production and purification of functional proteins.

The present invention belongs to the field of biopharmaceutical technology, and specifically relates to a method for preparing GLP-1 or its analogs. The present invention provides a leader peptide, and a fusion protein comprising the leader peptide. The leader peptide or fusion protein is used to prepare a semaglutide precursor polypeptide, and the results show that the yield of the prokaryotic expression fusion protein can reach 26g / L, and the purity of the precursor polypeptide obtained after enzyme cleavage is higher than 95%. The precursor polypeptide is further side-chain modified and connected with a dipeptide to efficiently prepare semaglutide.

The invention relates to preparation and application of umami peptide from procambarus clarkii, and belongs to the technical field of food biology. A preparation method of umami peptides from procambarus clarkia is characterized by comprising the following steps: firstly, separating and purifying polypeptides in a shrimp meat taste extract, predicting peptide activity through a database, carrying out molecular docking and molecular dynamics simulation method characterization, and finally identifying two potential umami peptides, namely LAEPLTFN and YGGEFPARPDN; the umami peptide is artificially synthesized, the fresh property of the umami peptide is verified through sensory evaluation and an electronic tongue method, and the synergistic effect of the umami peptide and other fresh substances is further evaluated. The umami peptide obtained by the method has a composite freshness increasing effect, enriches a fresh water source umami peptide library, and provides a new umami peptide raw material for development of composite freshness increasing seasonings.

The invention relates to the technical field of biology, in particular to multifunctional belly-expanding hippocampal peptide as well as a preparation method and application thereof. Comprising a polypeptide with an amino acid sequence as shown in SEQ ID NO.1. The hippocampus antioxidative peptide is prepared by adopting an ultrahigh pressure pretreatment and enzymolysis technology, the adopted extraction process is simple in route, and the time and the production cost are effectively saved; an animal model is utilized to prove the anti-oxidation effect and the effect of improving male reproductive disorder and testis injury of the multifunctional belly-expanding hippocampal peptide; and on the basis, a novel peptide fragment with high activity, no toxicity and no sensitization is obtained.

The invention relates to the field of preparation and application of biological peptides, in particular to a swelling hippocampal peptide and application of the swelling hippocampal peptide in preparation of anti-fatigue products. Five active peptide sequences with high biological activity are obtained through research, animal behavioral experiments prove that the belly distention hippocampal peptide has a remarkable anti-fatigue effect and can prolong the swimming exhaustion time and enhance the muscle strength, the anti-fatigue effect of the belly distention hippocampal peptide is verified, and a new way is provided for development of anti-fatigue hippocampal products.

The invention discloses tetrapeptide KA4 with an anti-fatigue function as well as a preparation method and application of the tetrapeptide KA4, and belongs to the technical field of biology. The tetrapeptide KA4 is screened from pacific salmon protamine enzymatic hydrolysate, the amino acid sequence is KYPA, and the tetrapeptide KA4 has strong binding capacity with KEAP1, AMPK and LDH, can significantly reduce the serum lactic acid content of a fatigue model mouse and significantly increase the load swimming time of the fatigue model mouse, has an anti-fatigue function, and can be applied to development of functional food for relieving fatigue.

Present invention teaches the method of using a keratin hydrolysis peptide (“KHP”) solution to enhance production yield and fruit quality of cucumber by selectively choosing specific weights of feathers and water, and treating the mixture to a high-temperature high-pressure hydrolysis process, the resulting solution is confirmed to contain at least 253 peptides and, at early growth stage, applied to the soil around and / or leaf surface of the cucumber plants. Optionally, the KHP solution can be diluted by water, as disclosed in the specification, before administering as taught herein.

The invention relates to the technical field of a preparation method of a type A recombinant botulinum toxin, in particular to a type A botulinum toxin obtained by adopting a gene recombination technology, and the amino acid sequence of the type A botulinum toxin is consistent with the sequence of the type A botulinum toxin prepared by extracting and purifying a wild strain Clostridium botulinum. According to the technical scheme, the single-chain protein of the botulinum toxin A sequentially comprises a botulinum toxin A light chain or a modified botulinum toxin A light chain, a connecting region and a botulinum toxin A heavy chain. According to the scheme, the high-quality recombinant botulinum toxin A is obtained after the single-chain protein is subjected to fermentation, crude purification, enzyme digestion and fine purification. According to the technical scheme, the problems of complex process, long period, high safety risk and the like in the existing process for preparing the botulinum toxin A from the wild bacterial strain clostridium botulinum can be solved, and meanwhile, the problem that the amino acid sequence consistent with that of the botulinum toxin A prepared from the wild bacterial strain clostridium botulinum cannot be obtained through the existing gene recombination technology is solved.

The invention discloses a method for promoting dissolution of eggshell membrane protein and preparing chelated calcium through high-pressure crushing. Comprising the following steps: separating and drying eggshells and eggshell membranes of egg shells, and respectively carrying out superfine grinding to obtain eggshell powder and eggshell membrane powder; adding water into the eggshell membrane powder, carrying out high-pressure homogenization, and centrifuging to obtain an eggshell membrane solution; adding eggshell powder into the eggshell membrane solution, adjusting the pH value to 1-3, and adding pepsase for reaction; after the reaction, adjusting the pH value of the eggshell membrane solution to 6.5-7.5, and adding trypsin for reaction; and after the reaction, inactivating the enzyme, centrifuging to take a supernatant, adding absolute ethyl alcohol into the supernatant for alcohol precipitation, and centrifuging to obtain a precipitate, namely the chelated calcium. The technical problem that the eggshell membrane protein is difficult to dissolve out is solved, and a new way is provided for industrial extraction of the eggshell membrane soluble protein.

The invention belongs to the field of antibacterial peptides, and particularly relates to an antibacterial peptide with a broad-spectrum antibacterial effect, an antibacterial product and application. The antibacterial peptide is named as CAMP1111NC, and is obtained by performing N-terminal acetyl end capping and C-terminal amino end capping on polypeptide shown in SEQ ID NO: 1. The antibacterial peptide has remarkable antibacterial activity on a staphylococcus aureus standard strain ATCC12600, pseudomonas aeruginosa PAO1, klebsiella pneumoniae, an acinetobacter baumannii standard strain ATCC19606, methicillin-resistant staphylococcus aureus ATCC33591, methicillin-resistant and gentamicin-resistant staphylococcus aureus ATCC33592 and acinetobacter baumannii bio-53272 resistant to various antibiotics, and the antibacterial peptide can be used for preparing the antibacterial peptide. The limitation of the traditional antibacterial peptide is effectively overcome.

Present invention teaches the method of using a keratin hydrolysis peptide (“KHP”) solution to enhance sweetness and flavors of tea leaves. By selectively choosing specific weights of feathers and water, and treating the mixture to a high-temperature high-pressure hydrolysis process, the resulting solution is confirmed to contain at least 253 peptides and then applied to the surface of tea leaves during sprouting stage and infused to the soil around the tea trees / plants; the increased content of L-theanine and polyphenol is separately tested and confirmed. Optionally, the KHP solution can be diluted by water, as taught in the specification, before applying to the tea leaves and the soil as taught herein.

The invention provides a solid-liquid combined synthesis method of semeglutide, which belongs to the technical field of semeglutide synthesis, and specifically comprises the following steps: segmenting a main chain of the semeglutide into three shorter polypeptide fragments, namely a fragment 4, a fragment 5 and a fragment 2 at sites 7-14, 15-22 and 23-37, and respectively synthesizing at the same time; performing solid-phase assembly on the fragment 4 and the fragment 5 to form 7-22 peptide fragments, namely a fragment 1, and after the fragment 1 is cut off from the resin, forming NHS ester at a C end; after the fragment 2 is assembled, selectively removing a protecting group A11oc on the Lys26, then connecting with a side chain for fatty acid treatment to form a fragment 3, and cutting off the fragment 3 from the resin; and connecting the NHS ester of the fragment 1 with the fragment 3 in a liquid phase reaction system. The crude semeglutide prepared by the synthetic method is relatively high in yield and purity. The refined semeglutide of which the purity is more than 99.3% and the content of single impurity is less than 0.1% can be obtained at high yield through a conventional purification means.

The invention discloses a peptide with a bone strengthening effect as well as a preparation method and application thereof, and relates to the field of biology. The casein is used as a raw material, the high-activity calcium ion chelating peptide and the directional preparation technology thereof are provided, the technology has the advantages of being high in efficiency, low in cost, easy to operate, good in stability and the like, the high-activity calcium ion chelating peptide can be prepared on a large scale, the utilization value of the casein is improved, and a new way is provided for development of functional natural calcium supplement products.

The invention provides a sweet protein mutant as well as a preparation method and application thereof. The mutant is obtained by amino acid mutation on the basis of an amino acid sequence as shown in SEQ ID NO.1 of sweet protein. The amino acid mutation type comprises at least one of K5D, V7R, D29N or E53R. The mutation is introduced into the amino acid sequence of the sweet protein, so that compared with the sweet protein corresponding to the original sequence, the sweetness of the mutant is obviously improved.

The invention relates to a silk fibroin biological material with high beta-fold content and a preparation method thereof, and belongs to the technical field of biological extraction. The method comprises the following steps: preparing a regenerated silk fibroin solution; adding an enzyme catalytic promoter and an enzyme into the regenerated silk fibroin solution for incubation; the enzyme catalysis auxiliary agent is selected from one or more of a metal ion catalyst, a zwitterionic surfactant, a functionalized ionic liquid and a calcium phosphate nano-cluster; and centrifuging, cleaning and drying the obtained product to obtain the silk fibroin biological material with high beta-fold content. The silk fibroin material has higher beta-folding amount through primary structure modification, the space structure is more crystallized, and the amino acid sequence is more regular and ordered. The silk fibroin material provided by the invention has excellent mechanical properties, efficiency and yield, and is a biological protein material with great development potential.

The invention belongs to the technical field of recombinant protein, and particularly relates to recombinant human fibronectin as well as an expression method and application thereof. The recombinant human fibronectin provided by the invention selects a fibronectin core functional domain III9-10 / III12-14, the core functional domain III9-10 / III12-14 is modified and transformed to obtain an encoding gene, and the encoding gene is transferred into escherichia coli and expressed to obtain the recombinant human fibronectin. The obtained recombinant human fibronectin has good stability, proliferation promoting activity and cell migration promoting capacity, can be applied to skin care products or cosmetics, and has important use value and practical significance.

The invention discloses an immune composition containing a fatty acid modified SpyCatcher protein and a preparation method of the immune composition, and belongs to the field of biological medicines. Wherein the SpyCatcher protein (LipoSC) can be self-polymerized into nanoparticles, the SpyCatcher protein (LipoSC) is covalently linked with an antigen containing SpyTag polypeptide through an isopeptide bond, so that the immunogenicity of the loaded antigen can be improved, and a coronavirus spike protein (S protein) receptor binding domain (RBD) is taken as an example. The immune composition containing the fatty acid modified SpyCatcher protein and the coronavirus RBD antigen disclosed by the invention can induce strong RBD specific immune response, and particularly can induce mucosal immunity and humoral immunity of antigen specificity as a mucosal subunit vaccine. The invention further provides a method for finishing fatty acid modification of the SpyCatcher protein in escherichia coli and a method for preparing various immune compositions by using the fatty acid modified protein.

The invention discloses sea cucumber gonad-derived antioxidant peptide as well as a preparation method and application thereof, and belongs to the technical field of food biology. The antioxidant peptide is obtained by carrying out enzymolysis and molecular docking screening on sea cucumber gonads, and comprises at least one of peptides with amino acid sequences as shown in SEQ.ID.NO.1-4. Wherein the docking energy of the SEQ.ID.NO.1 and the receptor SOD is-7.5 kcal / mol, the docking energy of the SEQ.ID.NO.2 and the receptor SOD is-7.5 kcal / mol, the docking energy of the SEQ.ID.NO.3 and the receptor SOD is-7.4 kcal / mol, and the docking energy of the SEQ.ID.NO.4 and the receptor SOD is-7.2 kcal / mol. Tests prove that the antioxidant peptide has high antioxidant activity and has wide application space in the field of functional food.