类似S-层蛋白的苏云金芽胞杆菌伴胞晶体蛋白基因的克隆  

CLONING OF PARASPORAL BODY PROTEIN GENE RESEMBLING TOS-LAYER PROTEIN GENES FROM BACILLU THURINGIENSIS CTC STRAIN

作　　者：孙明[1] 朱晨光[1] 喻子牛[1] 

机构地区：[1]华中农业大学生命科学技术学院农业部农业微生物重点实验室,武汉430070

出　　处：《微生物学报》2001年第2期141-147,共7页Acta Microbiologica Sinica

基　　金：国家自然科学基金资助!( 39870 0 36和 30 0 80 0 1 3)&&

摘　　要：芽胞杆菌CTC菌株被鉴定为苏云金芽胞杆菌 ,鞭毛血清型H2 ,幕虫亚种 ;产生卵圆形伴胞晶体 ,伴胞晶体蛋白为 1 0 0kD ;测定了该蛋白的N 末端序列 ,该序列与炭疽芽胞杆菌的细胞表面S 层蛋白具 92 %～ 93%相似性 ;根据Southern杂交制作了该晶体蛋白基因ctc所在位置的限制性酶切图谱 ,分别克隆了该基因 5′和 3′端所在的 2 9kbXbaI片段和 3 1kbClaIDNA片段 ,彼此间具 0 6kb重叠 ,通过拼接获得含完整ctc基因的克隆。含该基因的大肠杆菌与表达S 层蛋白的大肠杆菌具相似生长特征。初步表明CTC菌株的伴胞晶体由细胞表面S 层蛋白组成。苏云金芽胞杆菌区别于蜡状芽胞杆菌和炭疽芽胞杆菌的唯一标准是能形成伴胞晶体 ,由于S 层是细胞表面的结构成分 。Bacillus CTC strain was identified as \%Bacillus thuringiensis\% subsp.\%finitimus\% (serotype H2) and Pasteur Institute confirmed this identification.The parasporal body formed by CTC strain is oval shaped,and consists of 100kD protein.The deteermination of the N\|terminal amino acid sequence showed this protein shares 93% similarity to that of B.anthracis S\|layer proteins.The restriction map covering the related protein gene (\%ctc\%) was deduced according to southern hybridization.The DNA fragments containing the 5′ and 3′ end of \%ctc\% gene with 0 6kb overlap were isolated,respectively.Full length \%ctc\% gene was then constructed.\%B.thuringiensis\% is a specie similar to B.cereus and B.anthracis, and only can be distinguished by forming parasporal bodies.The growth of \%E.coli\% mainatining \%ctc\%gene is similar to that of \%E.coli\% expressing S\|layer protein gene.The above preliminary results showed that the parasporal body protein in CTC strain is a cell surface\|like protein.So identifying CTC strain as a specie of \%B.thuringiensis\% and the unique criterion for the identification of \%B.thuringiensis\% by forming parasporal body should be reconsidered.

关 键 词：细胞表面S-层 伴胞晶体 苏云金芽胞杆菌 蜡状芽胞杆菌群 基因克隆 蛋白质 

分 类 号：Q786[生物学—分子生物学] Q939124