43 results about "Clostridium tetani" patented technology

The invention relates to a method for a tetanus toxin receptor binding domain Hc to be subjected to high-level soluble expression in Escherichia coli through nucleotide sequence optimization. According to the sequencing result of a domestic C.Tetani virulent strain CMCC64008, the tetanus toxin receptor binding domain Hc sequence is analyzed and optimized, the optimized sequence is SEQ ID No.1 and the coded protein sequence is SEQ ID No.2. The synthesized Hc gene is linked into an expression vector pET32a(+) after undergoing double enzyme digestion, the recombinant Hc is subjected to high soluble expression in Escherichia coli and the target protein accounts for about 46% of the total protein in the supernatant undergoing bacteriociasis. After QFF column purification, phenyl hydrophobic column purification and SP column purification, the purity of the target protein can be more than 95% and the yield thereof is more than 300mg / L. The recombinant protein prepared by the method of the invention has good immunogenicity, can induce the mice to produce high-titre protective antibodies and can resist attack of high-dose lethal toxins. The method has extensive application prospect in large-scale high-level preparation of the tetanus toxin recombinant subunit vaccine Hc.

The invention relates to non-toxic tetanus toxin and clostridium perfringens beta toxin recombined fusion protein. By means of codon optimization, clostridium tetani fragments C and the recombined fusion protein containing multiple clostridium perfringens beta toxin mutants with amino acid mutation, the immunogenicity of two kinds of toxin protein is reserved to the maximum extent, and potential biosafety hazards caused by single amino acid mutation are avoided. The recombined fusion protein can be used for preparing unit vaccines of clostridium tetani, B type clostridium perfringens and C type clostridium perfringens; compared with a current commercial clostridium natural toxin inactivated vaccine in China, the recombined fusion protein has the advantages of being simple in preparation process, low in immunizing dose, excellent in vaccine potency and the like, the biosafety risk in the vaccine production process are greatly reduced, and the recombined fusion protein is an ideal candidate vaccine antigen for upgrading and updating the three kinds of clostridium toxin vaccines. When the recombined fusion protein is used for preparing a combined vaccine with other antigens, the combined vaccine can be prepared without increasing the use dose of the combined vaccine.

The invention discloses a method for preparing a tetanus toxoid vaccine. According to the process, with clostridium tetani strains as raw materials, the tetanus toxoid vaccine is prepared through the following steps of: culturing of tetanus toxoid, bacterium liquid separation, ultrafiltration and concentration, salting out, ultrafiltration desalting and the like. According to the method, firstly culture liquid is subjected to virus-free treatment and then refined, so that the porous channel plugging caused by accumulation of thalli and other impurity segments at a plate and frame membrane package during plate and frame filtering to remove thalli is reduced, and the smoothness during filtration is increased; toxoid protein and other allergens in the culture liquid are removed by changing the salting-out method; and as the desalting methods of the culture liquid after concentration and salting out adopt the tangential flow ultrafiltration method, the destruction of antigen caused by shearing of toxoid protein is reduced, and the protein precipitation is avoided. By utilizing the method, the time for preparing the tetanus toxoid vaccine is shortened, and the production efficiency is improved.