中国生物工程杂志

The I phase flagellin antigen of the three strong pathogenic strains Salmonella paratyphi A, Salmonella typhimurium, Salmonella Choleraesuis strain SGSC2461 is H-1a, H-1i and H-1c respectively. Three pairs of primers were designed in order to amplify the specifical gene fragments of epitopes with the length of 1088bp, 633bp and 1056bp by using PCR amplification technique. Utilized Linker of the primer and PCR amplification technique to connect the three antigenic determinant gene sequence in series,so the recombinant gene of flagellum is 2747bp altogether. Constructed the prokaryotic expression vectors pET-28a-F of flagellin recombination gene, and transfered the plasmid into E.coli BL21 then induced protein expression by IPTG. SDS-PAGE electrophoretic analysis that interest protein weighted 95Ku was expressed. It optimized the expression conditions. The percent of interest protein, which had been induced in terminal density 1mmol/L of IPTG under 37℃, is about 11.2% through thin-layer scanning analysis.Cracked the bacteria with supersonic wave, and purified cytorrhyctes which contained interest protein. Immuned the foot pads of gynaec Guinea Pig eight weeks aged. The titer of antibody detected by indirect ELISA was 1:512000, and the sensitivity was 8μg/mL.This is a foundation of research of detection of the fusion protein in the late stage.