关键词: 鼠疫耶尔森氏菌, caf操纵子, 克隆, 鼠伤寒沙门氏菌, 免疫

Abstract: The caf operon encoding F1 antigen of Y.pestis was amplified by PCR method, The PCR products were ligated to a vector plasmid, then transformed into Ecoli LE392. Some clones with caf operon obtained. These clones could express efficiently F1 antigen. The recombinant plasmids of those clones were extracted and transformed into S.typhimurium G30 by electroporation, some transformants were obtained, their expression level of F1 antigen was similar to those of Ecoli LE392 clones. The titer was up to 1∶80 as detected by IHA. These clones with caf operon could express efficiently in S. typhimurium, The clone immunized mice,the mice challenged with virulent 141 strain after 20 days. The survival was prolonged over that of negative control,our study provides pilot.