237 results about "Gram-negative bacteria" patented technology

The invention discloses an antibacterial peptide and application thereof, and belongs to the technical field of biology. The antibacterial peptide with an inhibition effect on various clinically common pathogenic microorganisms is obtained, and the antibacterial peptide comprises gram-negative bacteria such as escherichia coli, klebsiella pneumoniae, pseudomonas aeruginosa, acinetobacter baumannii, vibrio parahaemolyticus, salmonella gallinarum, salmonella typhimurium and enterobacter sakazakii, and gram-positive bacteria. The antibacterial peptide provided by the invention can be used as an antibacterial peptide, such as staphylococcus aureus, listeria monocytogenes and bacillus cereus, and the antibacterial peptide provided by the invention is novel in structure and easy to prepare.

The invention provides an additive composition containing a bioactive enzyme and a preparation method of the additive composition, and belongs to the technical field of biological enzymes. The preparation method comprises the following steps: fixing phytic acid and cyclodextrin on hydroxyapatite, modifying with tannic acid, reacting with dithiothreitol modified lysozyme to prepare an immobilized compound, adding 2, 2-dimethoxy-2-phenylacetophenone and methyl methacrylate, and carrying out irradiation reaction with an ultraviolet lamp to prepare the additive composition containing the bioactive enzyme. The broad-spectrum antibacterial property and the antiviral property of the lysozyme are greatly improved, the sterilization effect on gram negative bacteria is obviously improved, meanwhile, the stability of enzyme is greatly improved, the enzyme is not prone to inactivation, the preservation time of the enzyme is prolonged, the application effect of the enzyme is widened, meanwhile, the lysozyme has good killing capacity on oral bacteria and viruses, the addition of preservatives is reduced, and the cost is reduced. The cleaning effect and stability of the product are improved, tooth demineralization can be prevented, decayed teeth can be prevented, and wide application prospects are achieved.

The invention discloses an alveolar macrophage glycyrrhetinic acid liposome and a preparation method thereof, and belongs to the field of biological medicines. The surface of glycyrrhetinic acid lipidosome is modified with alveolar macrophage targeting molecules, so that the lipidosome can specifically target M1 alveolar macrophages induced by lipopolysaccharide serving as a main component of the outer wall of gram-negative bacteria, entrapped glycyrrhetinic acid is ingested by the alveolar macrophages, M2 polarization is specifically induced, and the specific targeting effect is achieved. Lung inflammatory injury caused by gram-negative bacteria is reduced, lung tissue injury and fibrosis caused by excessive inflammation are prevented, and great significance is achieved for pneumonia caused by gram-negative bacteria.

The invention discloses an application of NSC348884 in preparation of an antibacterial drug, the bacteria of the NSC348884 are gram-negative bacteria or drug-resistant gram-negative bacteria, and the gram-negative bacteria are acinetobacter baumannii, escherichia coli, pseudomonas aeruginosa or klebsiella pneumoniae; based on an antibacterial drug high-throughput screening technology, it is found from 1280 small molecule compounds that the benzimidazole compound NSC348884 has direct bacteriostasis and sterilization effects on gram-negative bacteria and drug-resistant gram-negative bacteria, and no drug resistance is generated after the benzimidazole compound NSC348884 is continuously applied for 14 days. Further research shows that NSC348884 can interfere with lipid synthesis of gram-negative bacterium cell membranes, inhibit formation of biological membranes and induce lipid metabolism disorder, so that bacteriostatic and bactericidal effects are achieved. In addition, the NSC348884 can also enhance the sensitivity of the drug-resistant bacteria to the imipenem and the polymyxin B.

The invention discloses a multi-target joint optimized antibiotic molecule design system and method applied to the field of biological medicine, and the method comprises the steps: obtaining FabI enzyme and AcrAB-TolC efflux pump structure data, extracting double-target space and physicochemical characteristics, and constructing a joint pharmacophore model containing a FabI inhibition domain and an efflux pump blocking domain; screening candidate molecules meeting a double-domain space matching threshold, screening high-affinity double-target molecules through conformation sampling and free energy calculation, and forming a lead compound library through multi-layer filtration of metabolic stability, membrane penetrability, quantum chemical properties and synthesis feasibility; carrying out electron effect, chain length or heteroatom fine tuning on dominant molecules through in-vitro bacteriostasis and efflux inhibition experiment feedback, and carrying out iterative optimization until MIClt is met; 2 [mu] g / mL and the efflux inhibition rate is gt; according to the present invention, the antibacterial effect and the drug resistance inhibition ability are significantly improved, the molecular synthesizability and the biological safety are ensured, and the engineering design new path is provided for the Gram-negative bacterium drug resistance crisis.

The invention discloses an antibacterial peptide IFD targeting gram-negative bacteria as well as a preparation method and application thereof. The amino acid sequence of the antibacterial peptide IFD is shown as SEQ NO.1, and a C terminal is amidated by adopting-NH2. The antibacterial peptide is obtained by modifying 119-132 fragments of human-derived MD-2 protein, and is prepared by site-specific mutagenesis, hydrophobic and hydrophilic sequence insertion optimization and solid-phase chemical synthesis. The antibacterial peptide has high antibacterial activity on Gram-negative bacteria (such as escherichia coli and salmonella typhimurium), the GM Gram-negative bacteria MIC reaches 3.63 mu M and is increased by 5.24 times compared with the original peptide, the targeting property is high, and the hemolysis rate 1t when the hemolysis activity is 128 mu M is low; 3%), the Gram-negative bacteria therapeutic index is as high as 76.1, and the Gram-negative bacteria can be used as a feed antibiotic substitute for preparing drugs for treating Gram-negative bacteria infectious diseases.

The invention discloses an antibacterial antifouling agent as well as a preparation method and application thereof. The preparation method comprises the following steps: carrying out chemical grafting on an amino terephthalic acid compound by adopting benzisothiazolinone to prepare a functional ligand; and carrying out a reaction on a metal salt and the functional ligand to prepare the antibacterial antifouling agent. The antibacterial antifouling agent disclosed by the invention shows broad-spectrum antibacterial activity on gram-negative bacteria and gram-positive bacteria, and has anti-algae performance and good biocompatibility; meanwhile, the antibacterial and antifouling agent is compounded into water-based acrylic resin, the obtained coating still has excellent antibacterial and anti-algae performance, the ligand engineering strategy effectively breaks through the bottleneck that traditional MOFs ligands are insufficient in antibacterial activity, and an innovative path is provided for developing long-acting, synergistic and practical MOF-based antibacterial and antifouling materials.

The invention relates to an antibacterial peptide CnCATH as well as a coding gene and application thereof, and belongs to the technical field of biomedicine. The novel antibacterial peptide is extracted from sika deer bone marrow, and the amino acid sequence is as shown in SEQ ID NO. 2. The antibacterial peptide shows strong antibacterial activity on various microorganisms including gram-negative bacteria, gram-positive bacteria and fungi, the sterilization speed of the antibacterial peptide is obviously improved compared with that of traditional antibiotics, the bacterial strain is not prone to drug resistance, endotoxin can be further neutralized, and the concentration of the endotoxin can be further reduced. The novel sika deer-derived antibacterial peptide provided by the invention has the advantages of small molecular weight, simple artificial synthesis, low drug resistance tendency and high broad-spectrum bactericidal activity, and provides a new strategy for microbial anti-infection treatment and prevention and treatment of diseases caused by endotoxin.

A peptidoglycan hydrolase LysPH1 having a broad-spectrum lytic activity, and a mutant and the use thereof, which belong to the technical field of biological formulations. An antibacterial peptide LysPH1-CP, a peptidoglycan hydrolase LysPH1 containing the antibacterial peptide LysPH1-CP and a peptidoglycan hydrolase mutant LysPH1-K containing the peptidoglycan hydrolase LysPH1 all have good thermal stability, and can broadly lyse both Gram-negative bacteria and Gram-positive bacteria. Moreover, the peptidoglycan hydrolase LysPH1 and the peptidoglycan hydrolase mutant LysPH1-K can be solubly expressed in Escherichia coli, and have high enzymatic activity. Therefore, the antibacterial peptide LysPH1-CP, the peptidoglycan hydrolase LysPH1 and the peptidoglycan hydrolase mutant LysPH1-K have good application prospects in the preparation of an anti-infective drug and the research and development of feed additives.

The application belongs to the field of polypeptides, and particularly relates to a marine-derived antibacterial peptide, a mutant thereof, an antibacterial composition and application. The application screens a marine-derived antibacterial peptide, and optimizes net charge, hydrophobicity and amphiphilicity of the antibacterial peptide through mutation. Through experimental testing, the four antibacterial peptides have differential antibacterial effects on different gram-negative bacteria, wherein the antibacterial peptide mutant shown in SEQ ID NO. 2 has the best antibacterial effect and low hemolysis, and has a positive application prospect.

The application discloses an antibacterial peptide RV15 and application thereof, and belongs to the technical field of biology. The amino acid sequence of the antibacterial peptide RV15 is shown as SEQ ID NO. 1. The antibacterial peptide RV15 provided by the application has broad-spectrum antibacterial activity, has a significant bacteriostatic effect on gram-positive bacteria and gram-negative bacteria, and has a long bactericidal duration. The hemolytic activity is very low, and the biological safety is good. The antibacterial peptide RV15 can be used for treating bacterial infection, and can also be applied to other scenes requiring bactericidal action or bacterial growth inhibition. The antibacterial peptide RV15 provided by the application has a short sequence, a small molecular weight and low chemical synthesis difficulty, and can save the production cost on a large scale.

The present application belongs to the technical field of artificial intelligence assisted drug screening, and particularly relates to a method for screening active molecules against carbapenem-resistant enterobacteriaceae based on a LightGBM algorithm, a medium and an apparatus. The method constructs a LightGBM integrated learning framework, fuses ADME rules optimized for the outer membrane barrier characteristics of gram-negative bacteria and multi-target molecule docking verification, effectively solves the problem of data imbalance caused by the scarcity of active samples and the huge compound library, and significantly improves the hit rate of screening. The present application also provides a computer readable storage medium and an electronic device. By storing and executing the above program, the present application can quickly and standardizedly identify anti-CRE candidate molecules from a large number of compounds, greatly reducing the computing power cost and time cycle of new drug research and development. The present application is designed to overcome the bottleneck of gram-negative bacterial outer membrane permeation, and provides an efficient, accurate and intelligent screening tool for combating CRE super-bacterial infections.

The invention relates to the technical field of organic chemistry, and particularly discloses an amide derivative containing a thiazole oxime structure as shown in a general formula 8 and a preparation method and application of the amide derivative. The derivative shows remarkable antibacterial activity on staphylococcus aureus, escherichia coli, pseudomonas aeruginosa and fluoroquinolone-resistant escherichia coli, particularly has a remarkable effect on gram-negative bacteria, has broad-spectrum antibacterial potential and can be used for preparing drugs for treating related bacterial infection, and the activity of part of compounds is superior to that of a control drug.

The invention relates to an antimicrobial peptide consisting of the amino acid sequence: RX1WILX2WLRTWX3X4 wherein X1, X2, X3 and X4 are independently selected from K and R, and wherein each amino acid is independently in the L or D configuration, or a salt or solvate thereof. The use of said antimicrobial peptide in the treatment of an infection caused by Gram negative bacteria, Gram positive bacteria, fungi, and / or yeasts, as well as the use of said peptide as an antimicrobial agent for the prevention of contamination of an article or a living tissue by and / or for the decontamination of an article or a living tissue from Gram negative bacteria, Gram positive bacteria, fungi, and / or yeasts are further aspects of the invention.

The application discloses a psoralen derivative or a pharmaceutical salt thereof, and a structure general formula of the psoralen derivative is shown in the following formula: The psoralen derivative is obtained by optimizing the structure of psoralen, and the antibacterial activity test is carried out on common gram-positive bacteria such as drug-resistant staphylococcus aureus and gram-negative bacteria such as escherichia coli and klebsiella pneumoniae, and it is found that the compound or the pharmaceutical salt thereof has excellent anti-drug-resistant bacteria, anti-inflammatory and anti-tumor activities, and has good development value in preparation of anti-infection treatment drugs, anti-inflammatory drugs and anti-tumor drugs.

The invention discloses a pearl sac antibacterial peptide and application thereof, and belongs to the technical field of biological medicine. The amino acid sequence of the gene is KRLF. According to the present invention, the theoretical molecular weight is 562.76 Da, the isoelectric point is 11.54, and the net charge is + 2 when the pH value is 7.0, and the antibacterial experiment result shows that the polypeptide has broad-spectrum and efficient antibacterial activity, and has significant inhibition effect on the proliferation of Gram-positive bacteria and Gram-negative bacteria. Safety evaluation experiment results show that the antibacterial peptide is beneficial to proliferation of keratinocytes and fibroblasts and is safe and non-toxic.

The invention discloses a chemotactic response type self-assembly antibacterial peptide and a preparation method and application thereof, the antibacterial peptide comprises: (a) a targeting module, the amino acid sequence of which is selected from KPRSVS or a variant thereof, GPLVPRG or a variant thereof, and GPLGVRG or a variant thereof; (b) a self-assembly module which is composed of hydrophobic residues and hydrophilic residues which are alternately arranged and forms beta-folding driving nanofibers; (c) an inflammation response module which is selected from a histidine enrichment region, an ROS sensitive group or an MMP protease cleavage site and is used for responding to an inflammation microenvironment and enhancing target site enrichment; (d) a stability enhancing module comprising at least one of D-type amino acid modification, N-terminal PEG4 connection or cyclization structures. The antibacterial peptide disclosed by the invention has chemotactic effect on an inflammatory microenvironment, can accurately identify gram-negative bacteria, is triggered in the inflammatory environment, and plays an accurate bactericidal effect on various pathogenic bacteria.

The invention discloses a self-assembled nano-capture antibacterial peptide KIL4 and a preparation method and application thereof, and belongs to the technical field of biology, and the amino acid sequence is shown as SEQ ID No.1. The preparation method comprises the following steps: adopting an alpha-spiral heptapeptide repetitive sequence (abcdefg) 4 template, and selecting lysine to provide positive charges at positions b and c; isoleucine and leucine are respectively filled to a position a and a position d to provide intermolecular hydrophobic force, and lysine and glutamic acid are selected to be respectively filled to a position e and a position g to provide intermolecular electrostatic force; the position f of the center of the hydrophilic surface of the polypeptide is filled with tryptophan to optimize the hydrophobicity of the polypeptide, on the basis, the sequence is repeated for four times, and the invention further discloses application of the polypeptide in preparation of drugs for treating gram-positive bacteria or / and gram-negative bacteria infectious diseases. The antibacterial peptide disclosed by the invention has dual effects of resisting bacteria and capturing bacteria, has excellent biocompatibility, and provides an effective technical support for developing novel antibacterial drugs.

The present application relates to the field of biomedicine technology, and in particular to the use of an antithrombotic small molecule compound BPTU (CAS No. 870544-59-5) as a colistin adjuvant for synergistic anti-Gram-negative bacteria, wherein the antithrombotic small molecule compound BPTU comprises a compound as shown in Formula I; the use of the antithrombotic small molecule compound BPTU as a colistin adjuvant for synergistic anti-Gram-negative bacteria, BPTU and colistin have a synergistic antibacterial effect on Gram-negative bacteria, the outer membrane of Gram-negative bacteria can act as a drug barrier, and colistin has membrane-breaking activity, and colistin breaks the barrier effect of the cell membrane to assist BPTU in entering the cell to exert its antibacterial activity. Therefore, the combined use of the antithrombotic small molecule compound BPTU and colistin has broad application prospects in the treatment of Gram-negative bacteria.

The application discloses a complex preparation containing bovine lactoferrin and lyticase and application thereof, and belongs to the technical field of biology. The preparation is composed of bovine lactoferrin and streptococcal lyticase, and both are prepared through a baculovirus-insect cell eukaryotic expression system. Researches show that the complex preparation has a significant synergistic antibacterial effect. The complex preparation not only can effectively inhibit a plurality of gram-positive bacteria, but also can overcome the limitation that single streptococcal lyticase has weak activity on gram-negative bacteria, and significantly enhances the inhibiting effect on escherichia coli and salmonella. Especially, the complex preparation still has clear in-vitro antibacterial activity on multi-drug resistant escherichia coli such as ciprofloxacin and doxycycline, thereby providing a new way for developing a new type of drug for resisting drug-resistant bacteria.

The application discloses copper porphyrin doped COFs, a preparation method and application thereof. The preparation method of the copper porphyrin doped COFs is as follows: 1) preparation of copper porphyrin modified aldehyde monomers; and 2) preparation of copper porphyrin doped COFs. The copper porphyrin doped COFs disclosed by the application can inhibit gram-negative bacteria and gram-positive bacteria under dark conditions; and under the irradiation of 100 mW / cm 2 of white light, efficient sterilization of the gram-negative bacteria and the gram-positive bacteria is realized within 90 min.

The invention belongs to the technical field of medicines, and discloses a near-infrared fluorescent probe Cy-NEO-Leu for leucine aminopeptidase responsiveness as well as a preparation method and application of the near-infrared fluorescent probe Cy-NEO-Leu. The parent nucleus of the probe is of a heptamethyl cyanine structure, and the probe has high molar absorption coefficient, high fluorescence quantum yield and excellent phototherapy characteristics. The introduction of a neomycin group can increase the water solubility of the probe, and a neomycin multi-ammoniation structure exists in a polycation form under physiological conditions and can target negatively charged cell walls of gram-negative bacteria, so that the probe Cy-NEO-Leu is enriched around the bacteria, can be specifically recognized by leucine aminopeptidase and can be hydrolyzed and activated; and photo-thermal and photodynamic sterilization effects are achieved under laser irradiation. Due to the good biocompatibility, the remarkable active oxygen generation capacity, the excellent photo-thermal conversion efficiency and the unique property of accurately targeting bacteria, the Cy-NEO-Leu is expected to play an important role in a photo-thermal / photodynamic combined treatment scheme, and is used for resisting diseases caused by bacteria and biological membranes and accelerating the healing process of wounds.

The invention belongs to the technical field of antibacterial peptides, and particularly relates to an antibacterial peptide Z34B3 and application thereof. The amino acid sequence of the antibacterial peptide Z34B3 provided by the invention is shown as SEQ ID NO: 1, the secondary structure is an alpha helix, the molecular weight is small, and the antibacterial peptide Z34B3 can change the cell membrane permeability of various gram-negative bacteria including pasteurella multocida, escherichia coli and acinetobacter baumannii, inhibit the generation of cell membranes and play antibacterial and bactericidal roles. Moreover, the antibacterial peptide Z34B3 provided by the invention has low hemolytic activity and no cytotoxicity, and can be applied to preparation of products with bacteriostatic and bactericidal effects and preparation of drugs for preventing and / or treating bacterial infectious diseases. Furthermore, the C tail end of the antibacterial peptide Z34B3 is subjected to amidation modification, and compared with non-modification treatment, the stability can be improved.

The application belongs to the technical field of molecular biology, and particularly relates to a long oyster C-type lectin CgCLec-TM2 functional domain CRD recombinant protein and application. The amino acid sequence of the long oyster C-type lectin CgCLec-TM2 functional domain CRD recombinant protein is shown as SEQ ID NO. 1. The rCRD obtained by the application has binding capacity to various pathogen-associated molecular patterns (PAMPs), can bind and agglutinate various microorganisms, has a growth inhibiting effect on gram-negative bacteria Vibrio splendidus and Escherichia coli, and can be used for the development of bacteriostatic feed additives and new-type immune enhancers.

This disclosure relates to a cephalosporin antibacterial compound and a method for preparing the same. This cephalosporin antibacterial compound exhibits antibacterial activity against a variety of bacteria, including Gram-negative bacteria.

The invention discloses gram-negative bacterium lyase and application thereof, and relates to the technical field of biological medicine. The gram-negative bacterium lyase is a lyase lysin of which the amino acid sequence is as shown in SEQ ID NO.1 or a lyase lysin-Mix of which the amino acid sequence is as shown in SEQ ID NO.3. The gram-negative bacterium lyase is a lyase lysin of which the amino acid sequence is as shown in SEQ ID NO.1. According to the invention, a novel lyase lysin is excavated from a bacteriophage, and the lyase lysin is subjected to bioinformatics analysis and modification, so that a novel lyase, namely lysin-Mix, is prepared. A lyase activity detection experiment shows that the modified new lyase can penetrate through the outer membrane of gram-negative bacteria and has good cracking activity. The invention provides technical support for developing novel antibacterial drugs.

The invention belongs to the technical field of biology, and particularly relates to endolysin derived from staphylococcus warneri mild bacteriophage and application of the endolysin. The endolysin has a nucleotide sequence as shown in SEQ ID NO: 1 or a nucleotide sequence obtained after further optimization of the endolysin. The endolysin gene sequence is completely and successfully obtained on the basis of the staphylococcus warneri mild bacteriophage vBG3001, the endolysin protein (endolysin 65) is successfully expressed and purified, and the endolysin protein has an inhibition effect on the growth of a gram-positive bacterium bacillus velezensis and a gram-negative bacterium burkholderia. The staphylococcus warneri mild bacteriophage perforin gene and endolysin gene are co-expressed in escherichia coli, so that the staphylococcus warneri mild bacteriophage has relatively strong bactericidal activity on host escherichia coli. The effects provide a theoretical basis for prevention and treatment of gram-negative pathogenic bacteria.

The present application relates to antibacterial active peptide technology, aiming to provide a kind of Lactobacillus reuteri Small molecule antibacterial peptide and its tandem repeat derivative peptide application.The present application provides the small molecule antibacterial peptide X507 with amino acid sequence as shown in SEQ ID NO.1 and antibacterial peptide X507-4 as shown in SEQ ID NO.2;The latter is the derivative prepared by repeating tandem based on the amino acid sequence of antibacterial peptide X507, which consists of 12 amino acids.The antibacterial peptide and derivative peptide provided by the present application have less amino acids, simple synthesis, low cost, easy industrialization and application;Gram-negative bacteria, gram-positive bacteria and corresponding drug-resistant bacteria growth have broad-spectrum antibacterial activity, good stability, no obvious cytotoxicity advantage, for solving the problem of drug-resistant bacteria infection, promoting green medical treatment and the development of breeding has important significance.

The present invention discloses a CXCL-BPI fusion protein that can be used for treating Gram-negative bacterial infections, a coding nucleic acid thereof, a method for expressing and preparing the same, and a use thereof in the manufacture of a pharmaceutical composition for treating Gram-negative bacterial infections. The CXCL-BPI fusion protein comprises a human ELR+CXC chemokine and a bioactive fragment of N-terminal domain of human BPI, and has the dual functions of both ELR+CXC chemokine and BPI, with ability of binding to LPS and directly killing Gram-negative bacteria, and also inducing chemotaxis and promoting phagocytes to target, bind to and phagocytize Gram-negative bacteria. The mechanism of action of the fusion protein can overcome Gram-negative bacterial drug resistance.

The present application relates to a kind of polypeptides with inhibitory activity to gram-negative bacteria and gram-positive bacteria represented by escherichia coli and staphylococcus aureus derived from Daqu.The amino acid sequence is Tyr-Pro-Leu-Gly-Gln-Gly-Ser-Phe-Arg-Pro.Polypeptide YPLGQGSFRP has good inhibitory activity to gram-negative bacteria and gram-positive bacteria, as natural safe antibacterial agent, it has good application prospect in preparing medicine and / or health care product for preventing and / or reducing intestinal infectious disease caused by escherichia coli and staphylococcus aureus.