42 results about "Colicin" patented technology

The present invention discloses an artifically-combined antimicrobial engineering polypeptide. Said polypeptide is formed from pathogen signal transducing polypeptide and colicine capable of forming ion channel or its water porous channel structural domain. Its molecular structure is connection of carboxyl terminal of colicine or its water porous channel structural domain and amino terminal of signal transducing polypeptide or connection of its amino terminal and carboxyl terminal of signal trasducing polypeptide. molecular weight of the polypeptide is 10000-63000, it can be respectively connected with signal transducing polypeptide of different pathogen, and can form the engineering polypeptide resisting said pathogen. Said invented polypeptide preparation method utilizes the point mulation technique to insert the pathogen signal transducing polypeptide gene into the site selected by colicine gene loaded in the engineering plasmid, then transports the mutation plasmid into engineering bacterium to make production. It does not make bacteria produce resistance to drug, and can change signal tranducing polypeptide to produce any antibiotic.

Chimeric proteins are expressed, secreted or released by a bacterium to immunize against or treat a parasite, infectious disease or malignancy. The delivery vector may also be attenuated, non-pathogenic, low pathogenic, or a probiotic bacterium. The chimeric proteins include chimeras of, e.g., phage coat and / or colicin proteins, bacterial toxins and / or enzymes, autotransporter peptides, lytic peptides, multimerization domains, and / or membrane transducing (ferry) peptides. The active portion of the immunogenic chimeric proteins can include antigens against a wide range of parasites and infectious agents, cancers, Alzheimer's and Huntington's diseases, and have enhanced activity when secreted or released by the bacteria, and / or have direct anti-parasite or infectious agent activity. The activity of the secreted proteins is further increased by co-expression of a protease inhibitor that prevents degradation of the effector peptides. Addition of an antibody binding or antibody-degrading protein further prevents the premature elimination of the vector and enhances the immune response.

The invention relates to a novel polypeptide for resisting tumors caused by EB (Epstein-Barr) viruses, and application and a preparation method thereof, belonging to the fields of antineoplastic medicaments. The novel polypeptide is composed of a colicine allosteric polypeptide capable of forming ion channels, and an antibody polypeptide for resisting EB viruses or a mimic antibody polypeptide ofan anti-EB virus antibody, wherein the colicine allosteric polypeptide capable of forming ion channels is formed by mutating amino acid residues G11A, H22G, A26G, V31L and H40D with wild type colicine E1, Ia, Ib, A, B and N or a peptide chain of aqueous pore canal domain thereof; and the amino acid sequence of the anti-EB virus antibody is identical to that of a monoclonal antibody secreted by ATCC HB-168 hybridoma. The invention provides an improved medicament, which has the advantages of strong lethality, high safety, high specificity and low sensitization possibility, for treating tumors caused by EB viruses, and a preparation method thereof.

The present invention belongs to field of biology and medicine, and especially relates to a novel antibiotic, its nucleotide sequence, methods of construction and uses thereof. A novel antibiotic, wherein the end of any peptide of the allosteric colicin is connected linearly to the end of peptide of the Staphylococcus aureus pheromone AgrD I, AgrD II, AgrD III, AgrD IV or Staphylococcus epidermidis pheromone. Wherein the allosteric colicin being yielded by artificially mutating the amino acid residues G11A, H22R, A26G, V31L and H40K in the peptide chain of wild type Colicin E1, Ia, Ib, A, B, N, or their ion channel-forming structural domain. In comparison with the traditional antibiotics, the novel antibiotics in the present invention are not likely to lead to drug resistance and cause hypersensitivity reaction.

The present invention relates to two recombinant colicin expression systems, one utilizing a yeast expression system that produces a protein that is inexpensive to purify, and the other utilizing a plasmid expression system to be used as a probiotic culture. The recombinant colicins provide effective alternatives to conventional antibiotics and may be used to improve the efficiency of pork production, and the safety of its products.