129 results about "Minimum inhibitory concentration" patented technology

The invention belongs to the technical field of antibacterial peptides, and particularly relates to an antibacterial peptide and application thereof. The amino acid sequence of the antibacterial peptide is shown as SEQ ID NO: 1, the number of amino acids is small, the synthesis cost is low, the antibacterial peptide has high antibacterial activity on gram-negative bacteria and gram-positive bacteria, the minimum inhibitory concentration of the antibacterial peptide on acinetobacter baumannii, escherichia coli, pseudomonas aeruginosa and staphylococcus aureus is 4.68-37.5 mu g / mL, and the antibacterial peptide has the advantages of broad-spectrum antibacterial property, good stability and good application prospect. No obvious cytotoxicity and hemolysis effect exist; moreover, end-to-end amido bond cyclization is carried out, so that the antibacterial activity is further enhanced, the antibacterial effect on acinetobacter baumannii, escherichia coli, pseudomonas aeruginosa and staphylococcus aureus is enhanced by 2-4 times, and the minimum inhibitory concentration is reduced to 2.34-9.38 mu g / mL; after the end-to-end amido bonds are cyclized, the plasma stability and safety of the antibacterial peptide are further improved, and the cytotoxicity and hemolysis are reduced.

The invention belongs to the field of biological medicine, and particularly relates to an antibacterial peptide for inhibiting staphylococcus aureus and pseudomonas aeruginosa and application of the antibacterial peptide. The antibacterial peptide CAMP648NC is a novel cationic antibacterial peptide, the minimum inhibitory concentrations of the antibacterial peptide CAMP648NC to pathogenic bacteria staphylococcus aureus and pseudomonas aeruginosa are 16 [mu] g / mL and 32 [mu] g / mL respectively, the antibacterial peptide CAMP648NC has extremely low cytotoxicity, and after human skin keratinocytes HaCat and bronchial epithelial cells BEAS-2B are treated by the antibacterial peptide CAMP648NC with the concentration of 128 [mu] g / mL for 24 hours, the survival rates of 110.4% and 87.3% are still kept. Due to the characteristics, the compound shows extremely high medical drug antibacterial value, and alternative medicinal resources are provided for clinically resisting the two human pathogenic bacteria in the future.

The invention provides engineering lyase Art-15 with broad-spectrum antibacterial activity, antibacterial peptide NZ2114 and bacteriophage lyase PlySs2 are subjected to functional fusion through an optimally designed flexible linker, and an efficient bactericidal effect on Staphylococcus aureus (Staphylococcus aureus) and Streptococcus spp.) is achieved. The engineering lyase Art-15 has the advantages that the engineering lyase Art-15 has broad-spectrum antibacterial activity, the antibacterial peptide NZ2114 and the bacteriophage lyase PlySs2 are subjected to functional fusion through the optimally designed flexible linker, and the engineering lyase Art-15 has broad-spectrum antibacterial activity; the lyase Art-15 overcomes the defects of narrow host spectrum and insufficient splitting activity of the lyase through a synergistic destruction mechanism of targeting bacterial cell wall peptidoglycan. Experiments show that the minimal inhibitory concentration (MIC) of the lyase Art-15 on staphylococcus aureus in vitro is lower than 2 mu g / mL, the minimal inhibitory concentration of the lyase Art-15 on streptococcus agalactiae is lower than 1 mu g / mL, the minimal inhibitory concentration of the lyase Art-15 on streptococcus dysgalactiae is lower than 2 mu g / mL, and the sterilization rate of the lyase Art-15 can reach 97% or above within 30 minutes by 2 times of MIC. The lyase Art-15 disclosed by the invention has important application value in the fields of drug-resistant bacterium infection treatment, medical instrument disinfection and livestock breeding.

The invention provides a modified antibacterial peptide, and belongs to the technical field of antibacterial peptides. The invention provides a modified antibacterial peptide. The modified antibacterial peptide comprises at least one of a first antibacterial peptide, a second antibacterial peptide, a third antibacterial peptide, a fourth antibacterial peptide, a fifth antibacterial peptide and a sixth antibacterial peptide, the amino acid sequences of the first antibacterial peptide, the second antibacterial peptide, the third antibacterial peptide, the fourth antibacterial peptide, the fifth antibacterial peptide and the sixth antibacterial peptide are shown as SEQ ID NO.1-SEQ ID NO.6 in sequence. On the basis of prevotelin-2, the modified antibacterial peptide is obtained by reducing negative charge amino acid, increasing positive charge amino acid, introducing hydrophobic amino acid, adjusting or deleting an amino acid sequence and optimizing a polypeptide structure. In-vitro minimum inhibitory concentration determination results show that compared with an initial peptide, the modified antibacterial peptide has significantly enhanced antibacterial activity on bacteria and fungi, and also has an obvious bactericidal effect on clinical drug-resistant bacteria.

The invention relates to an enzyme response antibacterial carbon dot and a preparation method and application thereof.The carbon dot takes a copper-doped carbon dot as a core and is covalently grafted with a hyaluronic acid shell layer through amidation reaction to form a composite nano material Cu-CDs (at) HA, specifically, soluble copper salt and folic acid are subjected to a hydrothermal reaction to obtain the copper-doped carbon dot, carboxyl is activated through EDC / NHS in a buffer system, and the carbon dot is prepared. And performing grafting reaction with hyaluronic acid to obtain a target product. The hyaluronidase-containing antibacterial composition can be specifically degraded and release antibacterial components under the action of hyaluronidase, shows good bacterial responsive bactericidal performance, has the minimum inhibitory concentrations of 8 g / mL and 16 g / mL for staphylococcus aureus and escherichia coli respectively, and has peroxidase-like activity and free radical scavenging capacity. The antibacterial carbon dots can be used for preparing intelligent wound dressings, antibacterial coatings and other biomedical materials, and have the advantages of responsive drug release, efficient antibacterial property and promotion of wound repair.

The invention provides an antibacterial peptide CN-3 and application thereof, and relates to the technical field of peptide inhibitors. The amino acid sequence of the antibacterial peptide CN-3 is GPGGAWAAKVIS, and is as shown in SEQ ID NO. 1. The minimum inhibitory concentration (MIC) of the antibacterial peptide CN-3 to staphylococcus aureus and escherichia coli is 5.0 mg / mL. According to the antibacterial peptide CN-3 and the application thereof, the CN-3 has staphylococcus aureus and escherichia coli bacteriostatic activity, and plays a role by destroying bacterial cell membranes; cN-3 is not easy to generate drug resistance, low in cytotoxicity and high in cell selectivity, and can be used for preparing an antibacterial composition for treating staphylococcus aureus and escherichia coli infection.

The invention relates to the technical field of antibacterial peptides, in particular to application of an antibacterial peptide RV-18-ack in preparation of an antifungal product. The antibacterial peptide RV-18-acy disclosed by the invention comprises a polypeptide RV-18 of which the amino acid sequence is shown as SEQ ID NO. 1. The antibacterial peptide RV-18-ack is a polypeptide capable of forming an amphiphilic alpha helical structure, can form nanoparticles in a self-assembly manner, has broad-spectrum antifungal activity, can damage fungal cell membranes in a targeted manner to play a bactericidal role, shows a relatively good antibacterial role on candida albicans, has the minimum inhibitory concentration of 2.344-75 mu M, and is free of cytotoxicity and hemolysis; besides, the antibacterial peptide RV-18-ack contains 18 amino acids, and all the amino acids are L-type amino acids, so that the production cost is greatly reduced, and the antibacterial peptide RV-18-ack is expected to become a novel broad-spectrum antifungal candidate drug and has a good application prospect in the aspect of resisting super fungi.

The present invention provides use of a C-JUN N-terminal kinase inhibitor, SU3327, in the preparation of a medicament for enhancing the efficacy of polymyxin against bacterial infection, and use of a composition of SU3327 and polymyxin in the preparation of a medicament for an enhanced efficacy against bacterial infection, wherein the polymyxin is preferably Polymyxin E. The invention not only shows an enhanced antibacterial activity of polymyxin by SU3327 in synergy through minimum inhibitory concentration tests in checkerboard assays and in vitro bacterial growth curves, but also confirms the ability of SU3327 to enhance polymyxin along with its effectiveness in vivo in the experiments with a model of mice infected with drug resistant bacteria at the animal level. The invention provides a new use of SU3327 in enhancing antibacterial activities of polymyxin antibiotics, resolving the technical problems such as clinical resistance to polymyxin, low clinical therapeutic index of polymyxin, etc.

The invention relates to the field of antibiosis of natural products, in particular to application of geraniin in inhibition of staphylococcus aureus or a staphylococcus aureus biological membrane. The geraniin disclosed by the invention has a remarkable inhibiting effect on staphylococcus aureus, also has a remarkable inhibiting and clearing effect on a mature staphylococcus aureus biological membrane, and has the potential of being developed into a novel antibacterial drug. The effective concentration acting on a biological membrane is obviously lower than the direct minimum inhibitory concentration of geraniin to staphylococcus aureus. The inhibition characteristic of the geraniin on the biological membrane possibly has important value in solving the clinical biological membrane related drug resistance problem, and the geraniin can be used for treating bacterial infection disease recurrence caused by the stubborn biological membrane.

The invention discloses an antibacterial polypeptide AuGF and application of the antibacterial polypeptide AuGF in preparation of a medicine for treating and / or preventing bacterial infection. The amino acid sequence of the polypeptide is as follows: SEQ ID NO.1: GLFIKIIKIKIAKSF; the antibacterial polypeptide AuGF disclosed by the invention has broad-spectrum antibacterial activity, can effectively solve the problem of bacterial drug resistance, and has a remarkable bacteriostatic effect on various bacteria including staphylococcus aureus, streptococcus mutans, actinobacillus, methicillin-resistant staphylococcus aureus and the like; the compound provided by the invention has the advantages of simple preparation process and low cost, can play a significant role at low concentration, has low minimum inhibitory concentration on various pathogenic bacteria, has strong bacteriostatic ability, and is beneficial to reduction of side effects and improvement of drug safety; the antibacterial polypeptide AuGF can also be used as a bacteriostatic additive to be applied to articles of daily use, provides an effective bacteriostatic means for daily cleaning and skin care, and has a wide market application prospect.

The present invention relates to a method for screening compounds for bactericidal activity using thermostable luciferase and based on a real-time bioluminescence measurement. The present invention further relates to a method for determining the sensitivity of a bacterial sample originating from a subject suffering from a bacterial infection to a group of known antibiotics and to a method for assessing the minimum inhibitory concentration (MIC) of a bactericidal compound.

The invention discloses an antifungal peptide targeting fusarium oxysporum as well as a preparation method and application thereof, and belongs to the technical field of microorganisms. According to the present invention, the polypeptide specifically bound with Fusarium oxysporum is obtained through screening, and the sequence of the polypeptide is WYHRSHPQWNHW; the antifungal peptide WY-66-10 is formed by hybridizing and fusing the targeted structural domain and the weak-activity antibacterial peptide 66-10, the antifungal peptide WY-66-10 can kill fusarium oxysporum in a targeted manner, the minimum inhibitory concentration is improved by 30 times or more compared with that of the original polypeptide 66-10, and the targeted antifungal peptide WY-66-10 still keeps relatively weak cytotoxicity and hemolytic activity at the concentration of 128 mu M, and can be used for preparing the antifungal peptide WY-66-10. The method has good application values of targeting specific microorganisms, saving antibacterial resources and maintaining micro-ecological balance.

The present invention relates to a bacterial strain of Streptococcus salivarius with oral probiotic properties and a minimum inhibitory concentration of at least 500 ppm.

The invention belongs to the technical field of medical chemistry, and discloses a 5-O-carbon mould amine tylosin lactone derivative with a double-target combined antibacterial effect as well as a preparation method and application of the 5-O-carbon mould amine tylosin lactone derivative. The derivative is a compound as shown in a formula I, and pharmaceutically acceptable salt, eutectic, tautomer, polymorphic substance, solvate, prodrug or isotope labeled compound thereof. The compound can act on a bacterial ribosome 50S subunit and DNA topoisomerase IV at the same time, and shows an excellent antibacterial effect in an antibacterial activity test, and the minimum inhibitory concentration (MIC) reaches 0.0625 mu g / mL. The compound has the advantages of being high in antibacterial activity, wide in antibacterial spectrum and capable of achieving rapid sterilization, and a new choice is provided for developing drugs with antibacterial activity.

The invention belongs to the technical field of antibacterial peptides, and particularly relates to a self-assembled antibacterial peptide IL-9-Lau and application thereof. The self-assembled antibacterial peptide IL-9-Lau disclosed by the invention comprises a polypeptide main chain and lauric acid, the lauric acid is connected with a side chain amino group of lysine at the tail end C of the polypeptide main chain amino acid sequence through an amido bond. A polypeptide main chain is connected with lauric acid, self-assembly driving force is provided for the polypeptide main chain by means of strong hydrophobicity of lauric acid, the polypeptide main chain is in a nano-particle state under an electron microscope, the average particle size is 11.81 nm, and the critical micelle concentration is 129.18 mu M; moreover, the self-assembled antibacterial peptide IL-9-Lau is good in stability, free of obvious cytotoxicity and hemolysis and broad-spectrum antibacterial property, and the minimum inhibitory concentration of the self-assembled antibacterial peptide IL-9-Lau to acinetobacter baumannii, escherichia coli, pseudomonas aeruginosa and staphylococcus aureus is 1.2-4.7 mu M.

The invention relates to the technical field of antibacterial peptides, in particular to an antibacterial peptide RV-18-ack and application thereof in preparation of antibacterial products. The antibacterial peptide RV-18-ack provided by the invention comprises a main chain and fatty acid modified at a C end or an N end of the main chain, the amino acid sequence of the main chain is as shown in SEQ ID NO. 1. The antibacterial peptide RV-18-ack provided by the invention is a polypeptide capable of forming an amphiphilic alpha helical structure, has broad-spectrum antibacterial activity, shows a better antibacterial effect on acinetobacter baumannii, pseudomonas aeruginosa, escherichia coli and staphylococcus aureus, has the minimum inhibitory concentration of 1.17-4.69 mu M, and is free of cytotoxicity and hemolysis; all amino acids are L-type amino acids, so that the production cost is greatly reduced, and the compound is expected to become a novel broad-spectrum antibacterial candidate drug and has a good application prospect in the aspect of resisting super bacteria.

This invention discloses an antimicrobial peptide cAMP-1 derived from the intestinal microorganisms of wild rodents and its applications, belonging to the field of biotechnology. The amino acid sequence of the antimicrobial peptide cAMP-1 is shown in SEQ ID NO:1. The antimicrobial peptide cAMP-1 exhibits highly efficient, rapid, and safe antimicrobial activity against Streptococcus suis type II. It significantly inhibits bacterial growth even at low concentrations, with a minimum inhibitory concentration (MIC) of 16 µg / mL. Time-kinetic kinetics results show that the antimicrobial peptide can kill all Streptococcus suis type II within 30 min and 15 min at concentrations of 2×MIC and 4×MIC, respectively. Furthermore, within several times the effective concentration range, the peptide exhibits almost no hemolytic activity and low cytotoxicity within a safe dosage range, demonstrating its promising application as a novel anti-infective candidate drug.

The invention discloses an antibacterial peptide sesquidendrin and an application of the antibacterial peptide sesquidendrin. The invention specifically relates to eight sesquistigma polypeptide compounds. The compounds 1-8 show different degrees of antibacterial activity, the compound 2 has broad-spectrum antibacterial activity, the minimum inhibitory concentration of the compound 2 to staphylococcus aureus ATCC 6538 and bacillus cereus CMCC (B) 63301 reaches 20 [mu] g / mL, and the MIC value of the compound 2 to enterococcus faecium 160119481, salmonella typhimurium CMCC (B) 50071 and salmonella typhimurium CMCC (B) 50115 is 40 [mu] g / mL. As staphylococcus, bacillus, enterococcus and salmonella bacteria are common food-borne pathogenic bacteria which seriously threaten food safety, the compounds 1-8 can be used for preparing novel antibacterial peptides which are applied to the field of food safety preservation.

The application belongs to the technical field of non-antibiotic compounds as bacteriostatic agents, and discloses an application of a known non-antibiotic compound, cladrabine, in inhibiting the growth of multi-drug resistant Klebsiella pneumoniae. The application finds that cladrabine can inhibit the growth of multi-drug resistant Klebsiella pneumoniae, and the minimum bacteriostatic concentration reaches 64 mg / L. Further exploration of the bacteriostatic mechanism finds that after exposure to cladrabine, the permeability of the bacterial cell membrane is enhanced, and the macromolecular substances (nucleic acids and proteins) in the cell are excreted, causing the integrity of the bacterial cell membrane to be destroyed, and further causing the death of Klebsiella pneumoniae. The application proposes that cladrabine can destroy the cell membrane of bacteria, change the permeability of the cell membrane, has a good inhibitory effect on multi-drug resistant Klebsiella pneumoniae, and can be further applied to the preparation of related drugs.

The invention relates to the technical field of biology, and discloses an antibacterial peptide and application thereof. The amino acid sequence of the antibacterial peptide is as shown in SEQ ID NO: 1, the antibacterial peptide shows antibacterial activity to escherichia coli, staphylococcus aureus and candida albicans, especially shows high antibacterial activity to the candida albicans, the minimum inhibitory concentration is 64 [mu] M, and the antibacterial peptide has good antibacterial activity. The compound can be used for preparing bacteriostatic products such as bacteriostatic agents, bacteriostatic drugs and the like for resisting escherichia coli, staphylococcus aureus and candida albicans.

Heterocyclic compounds with a novel pyrazole thioamide-based NNSN structural motif, having highly effective zinc- or copper-activated toxicity against microbial infections at micromolar or nanomolar minimum inhibitory concentrations (MIC), and methods of making and using the same.

The invention relates to the technical field of biology, in particular to a pagrosomus major antibacterial peptide Pm-NK-lysin as well as a preparation method and application of the pagrosomus major antibacterial peptide Pm-NK-lysin. The amino acid sequence of the antibacterial peptide is as shown in SEQ ID NO: 1. The minimum inhibitory concentration of the antibacterial peptide to vibrio anguillarum is not higher than 8 [mu] g / ml, and / or the minimum inhibitory concentration of the antibacterial peptide to escherichia coli is not higher than 4 [mu] g / ml. The antibacterial peptide is prepared through a pichia pastoris expression system. The antibacterial peptide is applied to preparation of an antibacterial preparation. According to the invention, efficient secretory expression of recombinant Pm-NK-lysin is successfully realized by creatively utilizing a pichia pastoris eukaryotic expression system, and a protein purification process is optimized, so that sufficient sources of high-activity recombinant protein are guaranteed. The Pm-NK-lysin provided by the invention has an excellent killing effect on aquatic pathogenic bacteria. The antibacterial peptide Pm-NK-lysin is used for replacing or reducing the use of antibiotics to control the harm of aquatic bacterial diseases, has wide popularization and application values, and certainly has far-reaching significance for promoting the green and healthy development of the aquaculture industry.

The invention belongs to the technical field of biology, and particularly relates to an antibacterial peptide sourced from symbiotic methane-oxidizing bacteria in deep sea and application of the antibacterial peptide. The amino acid sequence of the antibacterial peptide is shown as SEQ ID NO. 1. The antibacterial peptide provided by the invention is a novel antibacterial peptide, has broad-spectrum antibacterial activity on a variety of gram-negative bacteria and gram-positive bacteria pathogens, such as pseudomonas aeruginosa, listeria monocytogenes, enterococcus faecalis and various vibrios, and has the minimum inhibitory concentration of 8.13-16.25 [mu] M. In addition, the antibacterial peptide has relatively weak hemolytic activity and relatively low cytotoxicity. The antibacterial peptide provided by the invention can replace antibiotics, is applied to prevention and treatment of various bacterial diseases, and is used as a safe and stable food additive or cosmetic preservative candidate substance.

The invention provides a macrolide compound and a preparation method and application of an intermediate compound of the macrolide compound, and belongs to the field of organic synthesis. The macrolide compound provided by the invention has the following chemical structure. The macrolide compound prepared by the invention is a compound with a 19-membered lactone ring structure, has a [5, 6]-tetrahydroindene ring structural unit and a (Z, E, Z) conjugated triene unit, and has a chemical structure completely different from that of MRSA drug-resistant bacterium antibiotics clinically used at present, such as polypeptide drugs (vancomycin and the like) and quinolone drugs (ofloxacin and the like), and the MRSA drug-resistant bacterium antibiotics can be used in clinical application. The macrolide is proved to have new drug-resistant bacterium resisting action targets and mechanisms. The macrolide compound provided by the invention has strong anti-MRSA activity, the minimum inhibitory concentration (MIC) is 1-2mg / mL and is equivalent to the anti-MRSA activity of vancomycin, and based on the strong anti-drug-resistant bacterium activity, the macrolide provided by the invention can be developed into a novel anti-drug-resistant bacterium drug. # imgabs0 #

The present invention relates to the technical field of the application of antimicrobial peptides, and particularly relates to a broad-spectrum bacterium-derived antimicrobial peptide cAMP-919nc and its application. The antimicrobial peptide cAMP-919nc is obtained by N-terminal acetylation modification and C-terminal amidation modification of the polypeptide shown in SEQ ID NO.1. This antimicrobial peptide exhibits excellent antibacterial effects against a variety of bacteria, especially the minimum inhibitory concentration against Staphylococcus aureus is as low as 4 μg / mL. Under different pH conditions, this antimicrobial peptide also shows significant bactericidal activity against the Gram-negative pathogenic bacterium Acinetobacter baumannii. In addition, this peptide has extremely low cytotoxicity, showing good safety. The present invention provides an antimicrobial peptide with excellent performance and has broad application potential, and can be used to develop various antimicrobial products such as antimicrobial drugs, disinfectants, and biological preservatives. The present invention opens up a new direction for the research and application of antimicrobial peptides and has important scientific and practical value.

This invention provides modified antimicrobial peptides, belonging to the field of antimicrobial peptide technology. The modified antimicrobial peptides include at least one of a first, second, third, fourth, fifth, and sixth antimicrobial peptide; the amino acid sequences of the first, second, third, fourth, fifth, and sixth antimicrobial peptides are shown sequentially as SEQ ID NO.1 to SEQ ID NO.6. Based on prevotellin-2, the modified antimicrobial peptides were obtained by reducing negatively charged amino acids, increasing positively charged amino acids, introducing hydrophobic amino acids, adjusting or deleting amino acid sequences, and optimizing the peptide structure. In vitro minimum inhibitory concentration (MIC) determination showed that, compared with the initial peptide, the modified antimicrobial peptides exhibited significantly enhanced antimicrobial activity against bacteria and fungi, and also showed significant bactericidal activity against clinically resistant 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.

This invention discloses a PKPD-guided method for treating porcine Pasteurella multocida with antibiotics. YDMS injection is used as the antibiotic, administered intramuscularly to pigs infected with Pasteurella multocida. The dosing regimen is adjusted based on in vivo PK / PD target values. The minimum inhibitory concentration (MIC) of YDMS against Pasteurella multocida is 0.06 μg / mL. PK / PD monitoring is performed using a combination of colloidal gold rapid detection and quantitative real-time PCR. This invention clarifies the three-level PK / PD target values ​​of YDMS against Pasteurella multocida and uses AUIC as the core quantitative indicator, avoiding the blindness of traditional empirical dosing. This ensures precise matching of drug concentration and infection severity, effectively reducing the risk of infection aggravation due to insufficient medication or cumulative toxicity caused by overdose, and significantly improving the consistency of treatment efficacy.

The invention belongs to the technical field of prevention and control of drug-resistant bacteria, and particularly discloses a composite bactericidal composition and application thereof in preparation of a reagent for killing aeromonas hydrophila oxytetracycline drug-resistant strains. The minimum inhibitory concentration of the epsilon-polylysine to an aeromonas hydrophila oxytetracycline drug-resistant strain is as low as 3.125 g / mL. Meanwhile, the sterilization mechanism of the epsilon-polylysine on aeromonas hydrophila oxytetracycline drug-resistant strains is discussed through metabonomics research. On the basis, the application finds that various exogenous small molecule metabolites such as 2-phenylacetamide and the like are combined with epsilon-polylysine for use, so that the absorption of drug-resistant bacteria on epsilon-polylysine can be promoted, the sterilization effect of the epsilon-polylysine is effectively enhanced, and the problem of drug resistance of bacteria is solved. Therefore, when the epsilon-polylysine and the exogenous small molecule metabolite are jointly applied, compared with the existing single antibiotic therapy, the epsilon-polylysine has higher activity and better safety and operability in preparation of the reagent for resisting the aeromonas hydrophila oxytetracycline drug-resistant strain.

The present invention discloses a novel antimicrobial peptide and its application. The present invention optimizes the structure of Epi-1, cuts off the non-α regions at both ends, and obtains a target antimicrobial peptide with a 16-amino acid sequence by replacing individual amino acids, thereby obtaining a novel antimicrobial polypeptide F-3 with a shorter sequence, higher antimicrobial activity, and better biocompatibility. A nucleic acid molecule encoding the antimicrobial peptide and an expression vector or recombinant cell containing the nucleic acid molecule are also provided. In vitro verification found that compared with the parent peptide, the derived peptide F-3 has higher antimicrobial activity or a higher bactericidal rate, and the minimum inhibitory concentration of F-3 is less than that of the parent peptide Epi-1; F-3 can also effectively inhibit or eliminate the formation of Enterococcus faecalis biofilm, and has low toxicity and good biocompatibility, and can be used to prepare drugs for preventing and treating diseases caused by Enterococcus faecalis infection; and the shorter amino acid sequence reduces the synthesis cost, and has good application prospects.