131 results about "Gram-negative bacteria" patented technology

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 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 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 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 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 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 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 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.

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 application of tegaserod maleate in preparation of an antibacterial drug synergist, and proves that the tegaserod maleate can produce a synergistic antibacterial effect with a plurality of commonly used antibacterial drugs (including tylosin, tetracycline, enrofloxacin, ampicillin and the like), can significantly enhance the antibacterial activity of the antibacterial drugs on gram-negative bacteria, and reduce the drug resistance of bacteria to the antibacterial drugs; the antibacterial composition composed of the tegaserod maleate and the antibacterial drugs can be used for preparing a drug for treating escherichia coli infection, and the synergistic antibacterial mechanism is mainly to destroy the inner and outer membrane permeability of bacteria, regulate the proton motive force of bacteria, inhibit the activity of bacterial efflux pumps, interfere with the energy metabolism homeostasis of bacteria and induce the bacteria to produce oxidative stress. The application provides a new technical strategy for the treatment of clinical escherichia coli infection, and has important clinical application value and industrialization potential.

The invention relates to the technical field of antibacterial composition preparation, in particular to a gynecological antibacterial composition and a preparation method thereof, and the gynecological antibacterial composition comprises the following raw materials: modified radix sophorae flavescentis, angelica sinensis, modified cortex phellodendri, radix paeoniae rubra, ligusticum wallichii, bombyx batryticatus, salvia miltiorrhiza, safflower carthamus, fructus cnidii, gallnut, calamine, pomegranate rind, catechu, rhizoma atractylodis, dragon's blood, fructus kochiae, borneol, alum, dried alum, purpurea sal ammoniac, magnesium stearate and starch. According to the invention, after the modified radix sophorae flavescentis is subjected to ethanol ultrasonic extraction, purification and micronization treatment, the dissolution rate and purity of effective components such as sophocarpidine are improved, the cell membrane structure of gram-negative bacteria such as escherichia coli can be quickly destroyed, and efficient bacteriostasis is realized; the modified cortex phellodendri is subjected to alkali dissolution extraction, acid precipitation purification and refined drying, berberine hydrochloride is efficiently enriched, the purity is improved, and the berberine hydrochloride can kill fungi such as candida albicans more accurately and strongly; and through high-temperature calcination and acetic acid activation, the calamine and the catechu are tightly combined at a microscopic level, so that the inherent convergence, granulation promoting and antibacterial effects of the calamine and the catechu are enhanced.

The invention belongs to the technical field of peptide antibiotics, and discloses an antibacterial peptide humAMP43 and polynucleotide, an expression vector, a host cell, a preparation method and application thereof, the antibacterial peptide humAMP43 is a polypeptide composed of 12 amino acids, and the amino acid sequence of the antibacterial peptide humAMP43 is shown as SEQ ID NO.1. The invention further discloses a preparation method of the antibacterial peptide humAMP43. The polypeptide is obtained through deep learning model screening and experimental verification, and meanwhile, the invention provides a coding gene, a recombinant expression system and an adaptive solid-phase synthesis method of the polypeptide. The antibacterial peptide has a broad-spectrum efficient inhibition effect on gram-positive bacteria and gram-negative bacteria, and the antibacterial rate can reach 98.6%. The invention further provides application of the antibacterial peptide in preparation of antibacterial agents, antibacterial infection drugs, food preservatives and feed additives, and a new candidate molecule is provided for development and application of the antibacterial peptide in medicine, agriculture and food industries.

The invention discloses an inflammation regulation sequence of dairy cow mastitis and application thereof, and belongs to the technical field of biology, the inflammation regulation sequence is a regulation sequence responding to a gram-negative bacterium inflammation signal, the regulation sequence is a promoter sequence of a CXCL2 gene and is shown as SEQ ID NO: 1, and the regulation sequence is a promoter sequence of a CXCL2 gene and is shown as SEQ ID NO: 2. A regulatory sequence responding to a gram-positive bacterium inflammation signal, which is a promoter partial sequence of the NLRP3 gene and is as shown in SEQ ID NO: 2; the regulatory sequence responding to a gram-positive bacterium inflammation signal is a promoter reverse complementary sequence of the TLR2 gene and is shown as SEQ ID NO: 3; the endogenous inflammation regulation sequence provided by the invention is composed of genome elements of the dairy cow, and no exogenous coding gene is introduced, so that potential risks caused by exogenous proteins are avoided.

The application belongs to the technical field of anti-infection of antibacterial peptide drugs, and provides an antibacterial peptide and application thereof.The antibacterial peptide takes an olefin functionalized amino acid as a monomer, and is obtained through a free radical polymerization reaction.The antibacterial peptide shows no inhibition on growth of gram-positive bacteria and gram-negative bacteria, but has an effect of clearing bacterial biofilms, and has excellent biocompatibility and no toxicity.The raw materials and reagents of the application are easy to obtain, and the preparation process is simple, so that the application has wide prospects in the fields of clinical infection treatment, environmental protection and food safety.

The invention belongs to the technical field of antibiotics, and discloses application of homovanillic acid in preparation of a bacteriostatic agent, application of homovanillic acid as a gram-negative bacterium antibiotic synergist and an antibacterial composition. The invention discloses homovanillic acid which has certain antibacterial activity on numerous bacteria, can be applied to preparation of a bacteriostatic agent and can be used for preparing the bacteriostatic agent with a wide antibacterial spectrum.

Provided are 13-membered macrolides for the treatment of infectious diseases. The 13-membered macrolides described herein are azaketolides. Also provided are methods for preparing the 13-membered macrolides, pharmaceutical compositions comprising the 13-membered macrolides, and methods of treating infectious diseases, and in particular, disease resulting from Gram negative bacteria using the disclosed macrolides. Formula (I)

The invention discloses a pseudomonas aeruginosa (Pseudomonas aeruginosa) T-5 with the preservation number of CCTCC (China Center for Type Culture Collection) NO: M 20251946, a microbial agent of the pseudomonas aeruginosa (Pseudomonas aeruginosa) T-5, and an application of the pseudomonas aeruginosa (Pseudomonas aeruginosa) T-5. The strain is gram-negative bacteria, cells are rod-shaped, bacterial colonies are large, the center of the strain protrudes and is milky white, and blue-green or tawny pigments can be generated; when the strain is cultured in an LB liquid culture medium under the conditions of 30 DEG C and 160 rpm, the strain enters a logarithmic phase in 2-4 h and enters a stable phase in 24 h, the OD600 value in the stable phase reaches 1.6 + / -0.1, and the viable count of fermentation liquor in 24 h is larger than or equal to 10 < 10 > CFU / mL; and the method is suitable for repairing a severe environment with composite organic pollution.

The invention provides a nano-enzyme system based on an Ag-polydopamine nano-microsphere (at) MOF-74 structure as well as a preparation method and application of the nano-enzyme system, and belongs to the technical field of biological medicines. The nano-enzyme system takes a polydopamine microsphere as a core, and an MOF-74 shell layer grows on the surface of the polydopamine microsphere in situ to form a composite microsphere with a core-shell structure; and by utilizing the reduction property of polydopamine, Ag nanoparticles are reduced in situ and uniformly dispersed in the MOF-74 framework, so that the composite nano material with the enzyme-like activity and the photo-thermal function is constructed. The system shows excellent horse radish peroxidase-like activity, and can effectively promote electron transfer between hydrogen peroxide and a substrate and catalyze a chromogenic reaction. Meanwhile, the composite system has good photo-thermal conversion performance, shows a remarkable photo-thermal sterilization effect on gram-negative bacteria and gram-positive bacteria, and can effectively inhibit and destroy the formation of bacterial biofilms. An in-vitro antibacterial experiment result shows that the MOF-74-based nano enzyme system has relatively high antibacterial activity.

The invention discloses a Brucella bacterium capable of generating a lipoid A vaccine adjuvant and an application of the Brucella bacterium. According to the invention, recombinant plasmids for expressing BacA and LpxL genes are constructed, and are transformed into Brucella through electric shock, so that a double-gene knockout strain is successfully obtained. By knocking out BacA, an ultra-long fatty acid chain of lipoid A is shortened, an organism is induced to generate an inflammatory reaction, and by knocking out LpxL, the inflammatory reaction is reduced, so that the effect of the immunologic adjuvant is achieved. LPS is extracted for in-vitro stimulation analysis, and it is found that the inflammatory response of double-gene deletion is reduced compared with that of single-gene deletion. Animal experiments show that double-gene deletion can induce an organism to generate good immune response and induce relatively high cellular immunity and humoral immunity, and a new thought is provided for research and development of gram-negative bacterium inactivated vaccines.

This application discloses a fluorescent probe for labeling the outer membrane of Gram-negative bacteria, its preparation method, and its application. The fluorescent probe uses polymyxin (with its hydrophobic tail and two amino acid residue pairs removed) as a targeting group specifically targeting the outer membrane of Gram-negative bacteria. This structure can specifically bind to the lipopolysaccharide structure in the outer membrane, and is then linked to the fluorophore rhodamine, which has switching properties, to design and synthesize a fluorescent dye. This fluorescent probe, possessing fluorescent switching properties, can be applied to super-resolution imaging of the outer membrane of Gram-negative bacteria.

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 an antibacterial peptide, a pharmaceutical composition and application, and belongs to the field of polypeptide medicines.The antibacterial peptide forms a novel annular conformation by introducing n-leucine and 2-aminobutyric acid to construct a parent nucleus structure. The affinity of the antibacterial peptide to the main component phosphatidylglycerol of a bacterial cell membrane is remarkably improved, is improved by 31 times or more compared with polymyxin B and is improved by 16 times or more compared with D50 peptide, and the selectivity of the antibacterial peptide to the main component phosphatidylcholine of a mammalian cell membrane is improved by hundreds of times or more compared with that of a control peptide. The polymyxin B peptide has extremely low toxicity to HK-2 kidney cells, and the biological safety of the polymyxin B peptide is obviously superior to that of polymyxin B and D50 peptide. The minimum inhibitory concentration of the antibacterial peptide to gram-negative bacteria is as low as 0.03 mu g / mL, is about 33 times higher than that of polymyxin B, and is 17-33 times higher than that of D50 peptide. The treatment effect of the antibacterial peptide is obviously superior to that of polymyxin B and D50 peptide in various infection models, and the antibacterial peptide is expected to be developed into a novel anti-infection drug and is used for preventing and treating various infections.

The invention relates to the technical field of agricultural biology, in particular to an alpha spiral mutant of granulysin with improved antibacterial activity and application of the alpha spiral mutant. The amino acid sequence of the alpha spiral mutant peptide of granulysin with improved antibacterial activity is as shown in SEQ ID No: 2. According to the present invention, the antibacterial activity of the granulysin mutant on different bacteria such as gram-negative bacteria salmonella typhimurium, escherichia coli and salmonella pullorum is enhanced;