宋氏I相/福氏1b痢疾双价抗原菌株的构建

A Bivalent Strain with the Characters of Shigella Flexneri lb and Sonnei

以菌体内重组方法将脱失了部分毒力基因片段的宋氏痢菌Ⅰ相抗原质粒诱动到已脱失140Md毒力质粒的福氏痢菌1b中,构建成兼具福氏及宋氏“O”抗原的二价菌株。该菌株不含编码卡那霉素抗性基因的Tn5;连续传25代仍对宋氏及福氏1b痢菌O抗血清呈凝集反应;质粒电泳图显示该二价菌株拥有供体菌赋予的75Md的质粒带。

An avirulent bivalent strain with both S. flexneri 1b and S. sonnei characters was achieved by transfering the large plasmid,which delected partial virulent gene fragment,encoding form I antigen of S. sonnei,into the recipient S. flerneri lb which had eliminated 140 Md virulent plasmid. There was no gene encoding for kanamycin resistent of F'lac::Tn5 in the bivalent strain. It maintained the agglutination properties with both anti-flexneri 1b and sonnei serum after 25 generations. Plasmid profiles showed that the bivalent strain possessed the 75 Md plasmid of S. sonnei 53. The stragegy about the construction of the bivalent strain was discussed.