108 results about "Antimikrobielle peptide" patented technology

The invention designs antimicrobial peptide with drug-resistance bacteria resistance activity and a novel structure. The antimicrobial peptide is obtained by modifying amino acid at N tail ends of natural antimicrobial peptide Anoplin and MPI respectively, then performing acetylization on the amino acid, and performing intermolecular connection on every two side chains of the peptide by replacing a -1H-1,2,3-triazole structure by one 1,4- under the 1,3-dipolar cycloaddition reaction of the click chemistry. The antimicrobial experiments and pyridinium iodide dyeing method experiments for staphylococcus aureus and escherichia coli of the conventional gram-positive bacterium and clinically separated drug-resistant staphylococcus aureus and drug-resistant escherichia coli show that the J-AM peptide and the J-AA peptide which are synthesized by the method are higher in antimicrobial activity, higher in drug-resistance bacteria resistance activity and higher in cytomembrane film penetration capacity and has an obvious drug-resistance advantage of avoiding a drug-resistance phenomenon caused by the general antibiotics; and therefore, the antimicrobial peptide has an extremely high application prospect in preparation of clinical treatment medicines.

The invention relates to a promoter replacement method for improving the yield of Bacillus subtilis surfactin, belonging to the biotechnology field. The DNA homologous integration technology is adopted for allowing a promoter Pspac to replace the promoter of a Bacillus subtilis fmbR surfactin synthase gene. The homologous sequence of 1081bp is obtained by amplification from an fmbR strain genome through the PCR method and connected to HindIII and BamH I restriction enzyme cutting sites of a plasmid pMUTIN4, a well constructed vector is converted into wild Bacillus subtilis fmbR, thereby realizing the replacement through the screening by an antibiotic culture medium and the molecular biology method. The method can directly improve an antimicrobial peptide production strain on genetics, thereby having potential application value in industry. The yield of the strain surfactin is improved by about 4.85 times, and the yield of the surfactin can be improved by about 10 times under the IPTG induction.

The invention discloses an antimicrobial peptide. The gene sequence of the antimicrobial peptide is a gene code sequence of a no-signal peptide of an antimicrobial peptide Snakin. The invention further discloses a method for preparing the antimicrobial peptide. The method comprises the following steps of (1) extracting the total RNA (Ribonucleic Acid) of capsicum leaf tissue, thereby obtaining a first chain cDNA (complementary Deoxyribonucleic Acid) for standby by adopting a reverse transcriptase; (2) carrying out PCR (Polymerase Chain Reaction) cloning to obtain the gene code sequence, denoted by an Sn gene sequence, of the no-signal peptide of the antimicrobial peptide Snakin; (3) forming recombination plasmids; (4) screening successfully-recombined plasmids denoted by pET-Sn; (5) transforming the successfully-recombined plasmids into competent cells BL21 (DE3) of Escherichia coli, carrying out induced expression by adopting IPTG, and meanwhile, secreting proteins; (6) carrying out ultrasonic-wave crushing on the competent cells which secrete the proteins in the step (5), carrying out centrifugation, and then, collecting the antimicrobial peptide from an supernatant. The method has the advantages that the antimicrobial peptide which does not contain signal peptides is obtained and has a killing effect on meloidogyne incognita chitwood.

The invention relates to the technical field of biological agents for livestock, in particular to multicomponent biological compound agent, which comprises, by weight, 94-98% of live bacteria preparation, 0.4-1.0% of fructooligosaccharide, 1.0-4.0% of fly larva antimicrobial peptide protein powder and 0.6-1.0% of herbs. The live bacteria preparation is prepared by graded fermentation. The herbs include 4 parts of radix astragali, 2 parts of root of Chinese pulsatilla, 2 parts of radix sophorae flavescentis, 2 parts of radix codonopsis and 1 part of licorice root, which are subjected to superfine grinding and mixing. The multicomponent biological compound agent is capable of effectively protecting the content of live bacteria in the live bacteria preparation, and also capable of guaranteeing the components to coordinate to function in immunization, so that physical disease resistance of livestock can be improved, and growth and development of livestock can be promoted. The multicomponent biological compound agent can be stored at normal temperature, and animal experiments show that the multicomponent biological compound agent placed at normal temperature for 3 months is still effective.

The invention provides a pichia pastoris-optimized oncorhynchus mykiss hepcidin gene sequence. Four recombinant plasmids pGAPZAlpha A / pPICZAlphaA-hep and pGAPZAlphaA / pPICZAlphaA-mhep are constructed by utilizing hepcidin genes or segments thereof, and are respectively electrotransformed into pichia pastoris GS115 and KM71H host cells to obtain a recombinant pichia pastoris strain, the recombinant pichia pastoris strain is subjected to culture expression to obtain expression polypeptide with the multi-bacteria resistance activity. The expression polypeptide has stronger bacteriostatic activity on escherichia coli, staphylococcus aureus and a part of fish pathogenic bacteria (vibrio parahaemolyticus 1.2164, aeromonas veronii X-1-06909, aeromonas hydrophila HA-336, and aeromonas veronii CL0901).

The invention is applicable to the technical field of genetic engineering and provides a yeast engineering bacterium, its preparation method and application. The yeast engineering bacterium of the present invention comprises a recombinant plasmid composed of a yeast shuttle plasmid and pokeweed antimicrobial peptide Pa-AMP05 gene. The sequence of the pokeweed antimicrobial peptide Pa-AMP05 gene is shown in SEQ ID NO:1. The yeast engineering bacteria of the embodiment of the present invention uses yeast as the expression system of pokeweed antimicrobial peptide Pa-AMP05 gene, which realizes safe and efficient expression of the gene and is suitable for industrial production.

A novel antimicrobial peptide is derived from myxinidin peptide. The novel antimicrobial peptides (i.e., myxinidin 2 and myxinidin 3) have low cytotoxicity for human cells while exhibiting an excellent antimicrobial activity, and exhibit an anti-inflammatory and a wound healing effect. Thus, they can be advantageously used as an effective ingredient of antibiotics, a cosmetic composition, a food additive, an animal feed additive, biopesticides, and a quasi-drug product or the like.

The invention discloses an antimicrobial peptide with complex biological activity and a preparation method and application thereof, and belongs to the technical field of molecular biology. The antimicrobial peptide is derived from scylla paramamosain, the amino acid sequence of the scylla paramamosain is shown in SEQIDNO.1 and the coding sequence of the scylla paramamosain is shown in SEQIDNO.2. The preparation method of the antimicrobial peptide includes the following steps that the total RNA of the scylla paramamosain is extracted to serve as a template, and retranscribing is performed to obtain cDNA; the cDNA is used as the template for PCR amplification to obtain nucleotide fragments containing the coding sequence of antimicrobial peptides, the amplified product and anexpression vectorare subjected to enzyme digestion, connection and transformation, escherichia coli engineering bacteria which can express recombinant antimicrobial peptides are constructed, the escherichia coli engineering bacteria are subjected to induction culture, and recombinant antimicrobial peptides are expressed. The antimicrobial peptides has good antimicrobial and antiviral activities, can be used forpreparing antimicrobial or antiviral agents, and has good application prospects.

The invention belongs to the technical field of medicines, and in particular discloses application of an antimicrobial peptide Protegrin-1 for preventing and controlling porcine reproductive and respiratory syndrome. According to the invention, an antimicrobial peptide Protegrin-1 is chemically synthesized according to an amino acid sequence of reported Protegrin-1 firstly; then, antimicrobial activity of the antimicrobial peptide Protegrin-1 is proved through an escherichia coli resistant DH5 alpha experiment, and researches on the antivirus activity of the antimicrobial peptide to HP-PRRSV are made through qRT-PCR, Western-Blot, cell supernatant TCID50 detection, IFA and other methods; and further the antivirus mechanism of the antimicrobial peptide is explained in virus adsorption and entrance into cell processes. The antimicrobial peptide Protegrin-1 is expected to be used as a novel medicine for preventing and controlling porcine reproductive and respiratory syndrome.

The invention provides methods to exert antimicrobial effects in prophylactic or therapeutic treatment of bacterial or fungal infections employing polypeptides that have affinity to microbial and fungal toxins.

The present invention relates to peptides comprising amino acids according to Formula I((X)l(Y)m)n  (I)wherein l, m and n are integers from 0 to 10; X and Y, which may be the same or different, are an amino acid selected from the group consisting of hydrophobic amino acids and / or cationic amino acids, together with methods for the use of the peptides in the treatment of microbial infections.

The invention relates to the technical field of biological engineering, relates to a recombinant human-derived antimicrobial peptide C16LL-37 and an application method thereof in streptococcus mutans bioactivity role, and analysis application of antimicrobial activity, targeting property, hemolytic property and other bioactivities of the recombinant antimicrobial peptide C16LL-37. A standard solid-phase synthesis technique is adopted for synthesis, an amino acid sequence of a human-derived antimicrobial peptide LL-37 is connected with 16 amino acid sequences CSPC16 of a C end of streptococcus mutans CSP through connecting body-GGG-connection, and the recombinant human-derived antimicrobial peptide C16LL-37 having specific targeting ability is synthesized. In conclusion, with research and development of the human-derived specifically targeted antimicrobial peptide C16LL-37, not only are the problems that natural antimicrobial peptides have broad antimicrobial spectra, easy generation of drug resistance, low biological efficiency, high difficulty of screening and the like solved, but also the shortcomings that chemically synthesized antimicrobial peptides have low chemical combination efficiency and fusion proteins are unstable are overcome. In addition, an AMP region of the C16LL-37 is derived from a human body, so the C16LL-37 has relatively high biological safety and lays a firm foundation for wide application in clinic in future.

Antimicrobial peptides and methods of use are provided.