42 results about "Defensin" patented technology

The invention relates to a chicken beta-defensin-6 mutant based on AI aided design, a recombinant expression system and application, and relates to the technical field of gene engineering and protein engineering. The chicken beta defensin-6 mutant has the following amino acids at the following five sites: lysine at the 33rd site, lysine at the 35th site, asparagine at the 49th site, arginine at the 61st site and proline at the 65th site. The chicken beta-defensin-6 mutant has high stability, activity and solubility, compared with wild chicken beta-defensin-6, the chicken beta-defensin-6 mutant has higher antibacterial activity and expression level, an efficient and safe antibacterial substitute is provided for livestock and poultry breeding, and the chicken beta-defensin-6 mutant can be widely applied to the fields of livestock and poultry breeding, animal health care and biological preservation.

The invention discloses a porcine beta-defensin-3 gene core promoter as well as a construction method and application thereof, and belongs to the technical field of gene engineering. The sequence of the core promoter is as shown in SEQ ID No.1, and the core promoter has remarkable promoter activity in porcine small intestine epithelial cells and can be regulated and controlled by nutrient substances sodium butyrate and glutamine. The invention also discloses a construction method for specifically amplifying the core promoter, which comprises the following steps: carrying out PCR (Polymerase Chain Reaction) amplification by taking porcine small intestine epithelial cell DNA (Deoxyribonucleic Acid) as a template, constructing a pMD-18T-pBD-3-P recombinant plasmid by taking upstream and downstream primers as shown in SEQ No.2-SEQ No.3, and amplifying by taking the recombinant plasmid as a template to obtain a core promoter fragment. The core promoter disclosed by the invention provides an excellent experimental system for researching a transcription regulation mechanism of the porcine beta-defensin-3 gene, the nutritional response characteristic of the core promoter provides a new platform for researching nutrition-immune interaction, and the core promoter has a wide application prospect in the field of healthy breeding of livestock and poultry.

The application provides a composite antibacterial peptide preparation, a preparation method and application. The composite antibacterial peptide preparation comprises a first defensin, a second defensin, a first cecropin and a second cecropin. The amino acid sequence of the first defensin is shown in SEQ ID NO:1, the amino acid sequence of the second defensin is shown in SEQ ID NO:2, the amino acid sequence of the first cecropin is shown in SEQ ID NO:3, and the amino acid sequence of the second cecropin is shown in SEQ ID NO:4. Compared with a single antibacterial peptide, the composite antibacterial peptide preparation has good stability, and shows good inhibitory effect on various gram-positive bacteria, gram-negative bacteria and fungi.

This invention discloses an oral vaccine against carp spring viremia virus, its preparation method, and its application. The oral vaccine is constructed by linking a carp spring viremia virus antigen protein and a Yellow River carp defensin protein via a flexible linker to form a fusion protein, which is then expressed in *E. coli* and enriched using a biological vector. The gene sequence encoding this fusion protein includes a truncated fragment of the carp spring viremia virus antigen protein gene (64-1389 bp), a fragment of the Yellow River carp defensin protein gene (70-201 bp without the signal peptide), and a flexible linker fusion gene connecting the two gene fragments. Compared with previously reported anti-SVCV vaccines, the oral vaccine against carp spring viremia virus prepared in this invention does not harm the fish during the entire immunization process, is simple to operate, safe and stable, and has a higher protection rate. Therefore, this oral vaccine provides broad prospects for the prevention and control of carp spring viremia.

This invention provides a compound drug for treating melioidosis, its preparation method, and its application. The drug comprises active components of traditional Chinese medicine, a bioactive preparation, and a pharmaceutically acceptable carrier. The active components of traditional Chinese medicine are primarily extracts of Scutellaria baicalensis, Coptis chinensis, Fagopyrum dibotrys, and Polygonum cuspidatum. The bioactive preparation includes polymyxin B, homoserine lactonease, and recombinant human β-defensin 3. The components work synergistically to construct a comprehensive intervention system covering all pathological stages, including biofilm disruption, sterilization, anti-endotoxin activity, intracellular bacterial clearance, immune regulation, and tissue repair. This system can effectively disrupt bacterial biofilms, kill multidrug-resistant strains, neutralize endotoxins, and eliminate latent intracellular bacteria, addressing the core pain points of existing melioidosis treatments, such as strong drug resistance, significant toxic side effects, and high recurrence rates. The preparation process of this invention is carried out under low-temperature and sterile conditions throughout, which fully preserves the stability of the active ingredients, making it suitable for industrial production. The drug can be prepared in various dosage forms, covering all clinical subtypes of melioidosis, and possesses clinical application value and promising prospects for widespread application.

The application discloses a full-gorge hard tick-derived defensin polypeptide and application thereof. The defensin polypeptide is IpDf3, and the amino acid sequence is shown as SEQ ID NO:1. The defensin polypeptide has different degrees of antibacterial activity on four gram-positive bacteria and two gram-negative bacteria. Bactericidal kinetics and scanning electron microscope experiments show that 3*MIC IpDf3 can quickly down-regulate the bacterial number by 1-4 logarithmic units in 60 min, and can cause irregular bulges or depressions on the surface of gram-positive bacteria, and even rupture of the cell membrane, indicating that the antibacterial mechanism may be closely related to the direct damage of the cell membrane. The defensin polypeptide not only has the activity of traditional defensin against gram-positive bacteria, but also has certain antibacterial activity against gram-negative bacteria, has a wide antibacterial spectrum, strong activity, fast bactericidal speed, and is expected to provide a candidate for the research and development of new antibacterial drugs, and has important application prospects.

The application discloses a traditional Chinese medicine exosome compound with anti-HPV and application thereof, and relates to the technical field of biotechnology.The compound comprises functional components secreted by a human cell co-culture system and a traditional Chinese medicine source extract, and the traditional Chinese medicine source extract is derived from a combined traditional Chinese medicine extract of Astragalus membranaceus, Isatis indigotica Fort., Honeysuckle and Sophora flavescens Ait., and relates to the technical field of biotechnology.The traditional Chinese medicine exosome carries natural active ingredients, and a multi-target anti-virus network is formed by beta-defensin-2 and interferon-gamma generated by co-culture with human cells.Compared with single traditional Chinese medicine extract or chemically synthesized nanoparticles, the HPV inhibition rate is increased by more than 170%, and the direct cytotoxicity of traditional Chinese medicine is reduced through an exosome delivery system, and the IC 50 >200ug / mL, which is significantly lower than that of a water decoction, and mucous membrane irritation experiments show no damage.

Provided is a [beta]-defensin-3 mRNA expression promoter comprising dipotassium glycyrrhizinate.

The invention discloses a preparation based on bug defensin as well as a preparation method and application thereof. The prepared porous fiber serves as a carrier, the high-temperature resistance of the bug defensin is improved, the porous fiber and phospholipid-chitosan-sodium alginate form dual protection, the activity of the bug defensin can be effectively guaranteed, the certain high-temperature-resistant activity is achieved, and the excellent feed processing adaptability is achieved. Besides, agricultural waste is adopted to prepare porous fibers, biocompatibility is higher, the porous fibers are loaded and then wrapped, the structure is not prone to being damaged, bad smells of the porous fibers can be covered, the food consumption is increased, immune regulation is participated, growth of animals is effectively promoted, on the whole, the mode of combining loading and wrapping is designed, the process is simple, and the cost is low. The entrapment efficiency is high, the antibacterial and antiviral activity is exerted, meanwhile, drug resistance is not prone to being generated, and the safety performance is high.

The application discloses a preparation method of enteric sustained-release defensin mesoporous silica nanoparticles. The enteric sustained-release defensin mesoporous silica nanoparticles prepared by the method have good defensin loading capacity, good responsiveness to trypsin and good enteric targeting and sustained-release defensin performance.

The application discloses a pig beta-defensin-3 gene core promoter and a construction method and application thereof, and belongs to the technical field of genetic engineering. The sequence of the core promoter is shown as SEQ ID No. 1, the core promoter has significant promoter activity in pig small intestinal epithelial cells, and can be regulated by nutrients such as sodium butyrate and glutamine. The application also discloses a construction method for specifically amplifying the core promoter, which comprises the following steps: performing PCR amplification by taking pig small intestinal epithelial cell DNA as a template, taking the upstream primer and the downstream primer shown as SEQ No. 2-SEQ No. 3 as the primer, constructing a pMD-18T-pBD-3-P recombinant plasmid, and taking the recombinant plasmid as a template to amplify a core promoter fragment. The core promoter provides an excellent experimental system for studying the transcriptional regulation mechanism of the pig beta-defensin-3 gene, the nutrient response characteristics provide a new platform for studying the interaction between nutrition and immunity, and the core promoter has a wide application prospect in the field of healthy breeding of livestock and poultry.

The invention discloses a novel defensin polypeptide sourced from sclerophyllum squarrosum and application of the novel defensin polypeptide. The novel defensin polypeptide is IpDf3, and the amino acid sequence of the novel defensin polypeptide is shown as SEQ ID NO: 1. The compound has different degrees of antibacterial activity to four gram-positive bacteria and two gram-negative bacteria. Bactericidal kinetics and scanning electron microscope experiments show that the IpDf3 of 3 * MIC rapidly down-regulates the colony count by 1-4 logarithmic units within 60 min, and can cause irregular protrusions or recesses on the surfaces of gram-positive bacteria and even rupture of cell membranes, which indicates that the antibacterial mechanism of the IpDf3 is possibly closely related to direct damage of the cell membranes. The defensin polypeptide not only has the anti-gram-positive bacterium activity of traditional defensin, but also has certain antibacterial activity on gram-negative bacteria, is wide in antibacterial spectrum, high in activity and high in sterilization speed, is expected to provide candidates for research and development of novel antibacterial drugs, and has important application prospects.

Provided herein is an antimicrobial composition for hygiene applications. The antimicrobial composition comprises an effective concentration of a cathelicidin LL-37 peptide fragment in combination with an effective concentration of non- ionic surfactant. The non-ionic surfactant is an Alkyl-Poly Glucoside (APG) or alcohol ethoxylates or both. The antimicrobial composition further comprises of a chelating agent like disodium EDTA, or malic acid or citric acid or GLDA or PES A. The composition achieves log reduction of at least 3 against Gram negative bacteria Pseudomonas aeruginosa, Escherichia coll and Gram positive bacteria Staphylococcus aureus, Enterococcus hirae.

Antimicrobial modified defensins or defensin-like peptides, modified C-terminal fragments of defensins or defensin-like peptides, and nucleic acids encoding the same are disclosed. Also disclosed are compositions comprising the defensin variant peptides and methods of using the same to control microbial infections and feed and food contamination in plant and vertebrate subjects.

Antimicrobial defensin peptide variants comprising modified C-terminal fragments of a defensin and nucleic acids encoding the same are disclosed. Compositions comprising the defensin variant peptides and methods of their use to control microbial infections of plants and vertebrate subjects as well as contamination of feedstuffs and foodstuffs are also disclosed.

This disclosure describes compositions and methods involved in tumor suppression and inhibiting infection of cells by pathogens. Generally, the compositions include an mRNA cargo that can provide a therapeutic benefit after being introduced into an epithelial cell. In some cases, the mRNA can encode a polypeptide. In some cases, the polypeptide can suppress epithelial cell proliferation. In other embodiments, the polypeptide can be involved in innate immunity. In various embodiments, the polypeptide can include cathelicin antimicrobial protein (CAMP), calprotectin, S100A8, S100A9, a β-defensin, S100A7, secretory leukocyte inhibitor, lipocalin 2, or lysozyme. In some embodiments, the mRNA can include a stabilizing moiety such as, for example, a 5′ cap or a 3′ extension.

The present application provides a black soldier fly defensin C-13326, the nucleotide sequence of the black soldier fly defensin C-13326 is shown as SEQ ID NO.1, and the application of the black soldier fly defensin C-13326 in inhibiting multiple drug-resistant Aeromonas sobria is also provided.The black soldier fly defensin C-13326 provided by the present application can be applied to the preparation of anti-drug-resistant Aeromonas sobria products to cope with the serious harm caused by drug-resistant Aeromonas sobria.

The present invention belongs to the fields of genetic engineering, bioengineering and biomedicine, and relates to a nucleic acid molecule encoding human defensin and a method and application for preparing human defensin. The nucleic acid sequence of the nucleic acid molecule includes any one of the following: (1) a sequence as shown in SEQ ID NO.2; (2) a nucleic acid sequence encoding human defensin obtained by substituting, deleting or adding one or more nucleotides to the sequence shown in SEQ ID NO.2; (3) a nucleic acid sequence having at least 80% sequence homology with the nucleic acid sequence described in (1) or (2) and having the same or similar functions. The method provided by the present invention uses a nucleic acid molecule encoding human defensin to construct a recombinant expression vector, which can recombinantly express human defensin hBD‑3, release the recombinant fusion protein into the culture supernatant, and facilitate protein purification. The recombinant human defensin obtained by the present invention has tissue regeneration function, and provides a new active molecule for the development of new drugs.

A method of using alpha defensins as a biomarker to aid in the diagnosis and treatment of ventriculitis. This biomarker can help improve diagnostic accuracy and decrease unwarranted empirical broad spectrum antibiotic use in suspected external ventricular drains (EVD)-associated ventriculitis.

The present invention relates to new peptides derived from HD-5 or HNP-4 having antimicrobial activity for use in modulating the microbiome of intestines, the lungs, the skin, the mouth, the eye, the ear, the vagina or other bodily surfaces and / or for use as an antimicrobial agent in a human or other mammals, as well as to medicaments containing these peptides.

The present invention relates to new peptides derived from HD-5 or HNP-4 having antimicrobial activity, said peptides for use in modulating the microbiome of the gut, lung, skin, mouth, eye, ear, vagina or other body surface, and / or as antimicrobial agents in humans or other mammals; and to medicaments containing these peptides.

The invention belongs to the technical field of mosquito-borne infectious disease prevention and control, and provides an effect of human defensin in inhibition of anopheles sterneri malarial. According to the invention, the human defensin 5 is injected into the body of the anopheles stellari model by adopting a method for constructing the anopheles stellari infection model, and the influence of the human defensin 5 on the malarial transmission capability of the anopheles stellari is evaluated. Results show that after entering the mosquito body, the human defensin 5 inhibits the development of plasmodium johnsonii in the anopheles stersonii at an early stage by stimulating the innate immunity of the mosquito, so that the purpose of reducing the malarial transmission capability of the anopheles stersonii is achieved.

The invention belongs to the field of polypeptides, and discloses an antibacterial peptide as well as a preparation method and application thereof. The antibacterial peptide is obtained by modifying the structure of the American oyster defensin derived peptide A4, and the antibacterial activity and stability of the original antibacterial peptide are further improved. Experiments prove that the antibacterial peptide disclosed by the invention has broad-spectrum antibacterial activity, and has good bacteriostatic activity on paratyphoid B and escherichia coli; pathogenic bacteria can be directly killed, and the effect is rapid; the hemolytic activity is low, the stability is relatively high, and the cytotoxicity is low. The antibacterial peptide provided by the invention is stable in preparation method and high in synthesis efficiency. The antibacterial peptide provided by the invention can be used as a therapeutic molecule for various common infections, and solves the increasingly serious problem of antibiotic drug resistance at present.

The invention belongs to the technical field of antibacterial peptides, and particularly relates to beta-defensin produced by Chinese softshell turtles as well as a coding gene and application of the beta-defensin. In order to provide the novel antibacterial peptide, the amino acid sequence of the beta-defensin produced by the Chinese softshell turtle is shown as SEQ NO.2, and the nucleotide sequence of the coding gene of the beta-defensin is shown as SEQ NO.1.

Clostridium difficile, reclassified as Clostridioides difficile, is a Gram-positive, spore-forming, anaerobic, and toxin-producing nosocomial pathogen. Since the first description of a C. difficile-associated disease (CDAD)-like case in 1892, C. difficile infection (CDI) has become a high-impact health care-associated infection throughout the world, especially in the developed countries. Described herein are methods of treating Clostridium difficile infection in a subject in need thereof by administering an amount of the engineered lysin-human defensin (LHD) protein(s) described herein.

The application discloses a screening method, platform and application of human intestinal alpha defensin 5 (HD5) receptor P2Y11, and belongs to the field of biological medicines. The method fuses multiple omics and experimental strategies, effectively solves the problems of complex receptor proteins and difficult independent identification of interactions, significantly improves the accuracy and reliability of defensin receptor identification, and provides a method system with strong universality and wide applicability for receptor research. The method successfully identifies the first cell receptor P2Y11 of HD5. The discovery of the P2Y11 receptor not only opens up a new perspective for in-depth understanding of the biological function and mechanism of HD5, but also provides a new potential target for the treatment of related diseases. In particular, for infectious diseases such as bacterial dysentery caused by Shigella and the like in which HD5 is involved, the P2Y11 receptor as a drug target provides a possibility for developing a new treatment scheme, and is expected to bring more effective treatment options for patients, and significantly improve the treatment effect and the quality of life.

The invention discloses a method for synthesizing recombinant human defensin with antibacterial activity by using chlamydomonas and application of the recombinant human defensin, compared with a traditional expression system, the method has the advantages in the aspects of cost effectiveness, expandability and safety, and the recombinant human defensin produced by the method shows effective antibacterial activity on various pathogenic bacteria and can be used for preparing the recombinant human defensin with antibacterial activity. Under the action of different temperatures, pH values and proteases, the compound has good stability, low hemolytic activity and extremely low cytotoxicity to mammalian cells. The invention also relates to the use of the recombinant human defensin as an antibacterial agent in a variety of applications, including medicaments, disinfectants and agricultural products.

Antimicrobial modified defensin or defensin-like peptides, modified C-terminal fragments of defensins or defensin-like peptides, and nucleic acids encoding them are disclosed. Compositions containing the defensin mutant peptides and methods of using them to control microbial infections in plants and vertebrates, and to control feed and food contamination are also disclosed.

The invention relates to the technical field of antibacterial peptides, and discloses a paris polyphylla defensin PpyDef1 gene, a protein and application thereof, the defensin gene PpyDef1 with an antibacterial function is screened and found from paris polyphylla for the first time, and a prokaryotic expression system is constructed to successfully express the PpyDef1 protein. It is proved that the PpyDef1 protein has significant inhibitory activity on a variety of bacteria and a variety of fungi. The antibacterial activity can be exerted in multiple fields, or disease-resistant breeding or biosensor preparation and the like can be carried out. The gene and the protein provided by the invention have wide popularization and application values.