11 results about "Cationic Antimicrobial Peptides" patented technology

The invention discloses an antibacterial peptide and application thereof in preventing and treating dental plaque and gingival problems, and belongs to the technical field of biology. According to the invention, two cationic antibacterial peptides LR18 and LR18-2 with amphiphilic alpha-helical structures are designed from the beginning. The two antibacterial peptides have good antibacterial and bactericidal activity on oral periodontal pathogenic bacteria (including fusobacterium nucleatum, porphyromonas gingivalis and streptococcus mutans), the minimum inhibitory concentration (MIC) is 62.5-500 [mu] g / mL, and the minimum bactericidal concentration (MBC) is 62.5-2000 [mu] g / mL. The structure is simple, the chemical synthesis difficulty is low, a high-purity product can be directly synthesized, the cell hemolytic activity is low, the safety is high, the product can be used for preparing oral antibacterial drugs and / or oral care products, and oral diseases are prevented and treated by inhibiting the growth of oral periodontal pathogenic bacteria.

The present invention relates to a peptide comprising an amino acid sequence of SEQ ID NO: 1 having antimicrobial activity, a polynucleotide encoding the peptide of the invention, a composition comprising the peptide of the invention and methods using the peptide or composition of the invention.

The invention relates to a compound preparation as well as a preparation method and application thereof. Specifically, the invention relates to a composite preparation, and the composite preparation is composed of a cationic antibacterial peptide Pt5-1c and cyclic diadenylic acid c-di-AMP, wherein the amino acid sequence of the cationic antibacterial peptide Pt5-1c is as shown in SEQ ID NO: 1; the cationic antibacterial peptide Pt5-1c is a derivative which is obtained by substitution, deletion or addition of one or more amino acids on a sequence shown in SEQ ID NO: 1 and retains a cell membrane penetrating function and an antibacterial function of the cationic antibacterial peptide Pt5-1c. According to the invention, the intracellular delivery efficiency and immune activation capability of c-di-AMP are greatly improved.

The invention discloses a compound feed additive containing cationic antibacterial peptide and application of the compound feed additive, and belongs to the technical field of animal nutrition and feed additives. The compound feed additive consists of the following components in percentage by mass: 10-30% of cationic antibacterial peptide, 5-15% of a saccharomyces cerevisiae viable bacteria preparation, 20-40% of butyric acid and 25-50% of milk powder. Through the synergistic effect of the antibacterial peptide, the probiotics, the acidifying agent and the food calling component, weaning stress can be effectively relieved, the feed intake and daily gain of piglets are remarkably increased, the feed conversion ratio and diarrhea rate are reduced, and intestinal health is improved. The additive is safe, free of residues and convenient to use, and is an ideal choice for replacing an antibiotic growth promoter, so that the additive has better application prospect and value in the technical field of animal nutrition and feed additives.

This invention discloses a cell membrane-modified inflammatory-responsive release nanoparticle, its preparation method, and its applications. The nanoparticles use a polylactic-co-glycolic acid (PLA) core, and their surface is modified with an immune cell membrane. The PLA is loaded with an antibacterial drug and modified with a positively charged material and a responsive switch. The immune cell membrane is obtained by isolating immune cells pre-stimulated by pathogens. The nanoparticles prepared by this invention possess the function of rapidly releasing drugs targeting homologous bacteria and sites of inflammation. During systemic circulation, they tend to target sites of inflammation caused by bacterial infection, rapidly releasing the drug under the action of the highly expressed MMP-3 enzyme at the site of inflammation, achieving efficient delivery of antibacterial drugs. This invention has shown good therapeutic effects in a mouse model of bacterial infection, providing not only an effective means for the in vivo delivery of cationic antimicrobial peptides but also a promising therapeutic strategy against Gram-negative bacterial infections.

The application provides a pH-responsive disintegrating amphiphilic dextran block polymer, a cationic antibacterial peptide nanodrug and application, utilizes the pH-responsive disintegrating amphiphilic dextran block polymer and the nanometer AMPs to utilize the electrostatic force, the N-B coordination bond force and the guanyl-π electron force to self-assemble into the cationic antibacterial peptide nanodrug, realizes the effective capture of the nanometer AMPs, not only improves the drug loading of the amphiphilic dextran block polymer, but also can protect the free amino group in the nanometer AMPs residue, improves the stability of the nanometer AMPs to protease, reduces the toxicity to normal cells and reduces the risk of hemolysis; and the cationic antibacterial peptide nanodrug gradually hydrolyzes under the weak acid environment of the infection site, so that the drug is enriched at the infection site and the bioavailability is improved, and a new solution is provided for overcoming the increasingly serious drug-resistant bacterial infection problem in clinic.

The invention discloses a preparation method of cellulose-based cationic antibacterial peptide, and relates to a preparation method of antibacterial peptide. The invention aims to solve the technical problems that the existing antibacterial peptide preparation is easy to degrade, poor in stability, low in probability of contact with pathogenic bacteria, low in immobilization technology efficiency and uncontrollable in structure. The invention provides a preparation method of cellulose-based cationic antibacterial peptide, which is characterized in that polylysine polypeptide with alkynyl which is synthesized in advance and azidation modified cellulose are subjected to covalent coupling by utilizing high efficiency and specificity of click chemical reaction to form a stable cellulose-polypeptide brush composite structure, and the cellulose-polypeptide brush composite structure is used for preparing the cellulose-based cationic antibacterial peptide. And finally, activating the antibacterial activity of the cations through a deprotection reaction. The antibacterial peptide CP-NH3 prepared by the method disclosed by the invention has extremely strong inhibition capability on spore germination of colletotrichum gloeosporioides, the germination rate can be reduced to 3.3% or below, and the antibacterial peptide CP-NH3 is obviously superior to a physical mixed antibacterial agent.

The application discloses a cationic cyclic peptide antibiotic based on Lugdunin. The cationic cyclic peptide antibiotic provided by the application has the membrane damage effect of a cationic antibacterial peptide, is easy to synthesize, and has better clinical application potential in resisting drug-resistant bacterial infection.

The invention provides a cationic antibacterial peptide with an amidated terminal as well as a preparation method and application of the cationic antibacterial peptide, and particularly belongs to the technical field of antibacterial peptide products. The invention provides a cationic antibacterial peptide with an amidated terminal, the amino acid sequence of the cationic antibacterial peptide is as shown in SEQ ID NO.1 or SEQ ID NO.2, and the C terminal of the cationic antibacterial peptide is amidated by adopting-NH2. The cationic antibacterial peptide directly acts on cell membranes of bacteria, has no specific target spot, can effectively reduce the risk of drug resistance in the use process, is high in antibacterial activity, low in hemolytic activity and easier in safety control, can be used in anti-infection clinical treatment, and has a wide development prospect.

The invention relates to an antibacterial glycopeptide and application thereof in treating intervertebral space infection. The glycopeptide has a structure as shown in a formula I, in the formula I, Bip represents a 4-biphenylacetic acid fragment, FF represents a dipeptide linker of two phenylalanine, X represents a cationic antibacterial peptide fragment of 6-8 amino acids, ManN represents a mannosamine fragment, Bip and FF are connected through an amido bond, the C end of FF is connected to the N end of X, and X and ManN are connected through an amido bond. The antibacterial glycopeptides of the present application can be used for the treatment of intractable infections, especially intervertebral space infections. The invention relates to Bip-FF-X-ManNI.

The invention provides a polyarginine protamine antibacterial peptide as well as a preparation method and application thereof, and belongs to the technical field of active peptide preparation. The polypeptide provided by the invention is separated and identified from sturgeon protamine, and the sequence rule and antibacterial activity of the separated target derived peptide are determined through amino acid sequence identification and in-vitro bacterial experiments. The polyarginine type cationic antibacterial peptide provided by the invention is prepared through acid extraction, alcohol precipitation, molecular sieve chromatography and cation exchange chromatography technologies, and in-vitro bacteriostasis experiments prove that the polyarginine type cationic antibacterial peptide can play a remarkable role in inhibiting and killing various bacteria including salmonella pullorum. The raw materials adopted by the invention are natural, high in safety and biocompatibility, and suitable for development of antibiotic substitute products and related drugs thereof.