【摘要】 ＤＥＳ诱变得到了三株球形芽孢杆菌无芽孢突变株Ｇ５ 、Ｃ４ 、Ｌ５ ，经显微观察、超微结构分析、生物测定、蛋白质ＳＤＳＰＡＧＥ 分析及质粒检测，观察到突变株Ｃ４ 、Ｌ５ 阻碍于芽孢形成的第Ⅱ期，突变株Ｇ５ 阻碍于芽孢形成的第Ⅲ期，其细胞中已有晶体形成，它对致倦库蚊幼虫的毒力明显高于仅有二元毒素蛋白合成、而无毒素晶体形成的突变株Ｃ４ 和Ｌ５ 。突变株Ｌ５ 消除了质粒，仍有二元毒素蛋白合成。Ｓｏｕｔｈｅｒｎ ｂｌｏｔ 分析表明含二元毒素基因部分ＤＮＡ 片段的探针仅与菌株Ｃ３４１ 、ＢＳ１０ 的染色体具有同源性，因此证明供试菌株的二元毒素基因定位于染色体上。更多还原

【Abstract】 Location of the binary toxin gene of B s C 3 41 and some biological characteristics of its asporogenous mutants which obtained by DES treatment were studied in this paper. Mutant C 4, L 5 with blocked at the stage Ⅱ of sporulation course were not possessed of any crystalline inclustion, but the binary toxin proteins were detected in their cells by SDS PAGE analysis. Another mutant G 5 which blocked at the stage Ⅲ of sporulation course formed parasporal crystal in the cells, and its toxicity to larvae of Culex quinquefasciatus was about 50 times highter than those of mutant C 4 and L 5. The result of curing plasmid and Southern blot analysis confirm the binary toxin gene of Bs C 3 41, Bs 1691 and Bs 10 locate on the chromosome.更多还原