痢疾志贺氏Ⅰ型菌毒素基因的克隆与表达  

CLONING AND EXPRESSION OF SHIGA-TOXIN GENE FROM SHIGELLA DYSENTERIAE TYPE Ⅰ

作　　者：李丰生[1] 黄培堂[1] 芮贤良[1] 黄翠芬[1] 

机构地区：[1]军事医学科学院生物工程研究所

出　　处：《微生物学报》1991年第6期420-425,共6页Acta Microbiologica Sinica

摘　　要：从痢疾志贺氏Ⅰ型菌 W30864株中提取染色体 DNA,用 EcoRI 完全酶解,电泳回收3—7kb 的片段,与载体 pUC19质粒连接重组,用大肠杆菌痢疾样毒素(SLT)基因探针进行筛选,得到了阳性重组子。实验表明志贺氏毒素基因是位于约4.5kb 的 EcoRl 片段上,包含毒素的 A 亚单位基因和 B 亚单位基因。在对克隆株的毒性测定中,采用 Hela-S3细胞试验,证明所产生的痢疾毒素具有杀死细胞的能力。此毒素可引起肠积水和充血,可使小鼠肢体麻痹并致死,克隆重组株的痢疾毒素产量是亲本野生株 W30864的16倍。此外,实验中还对克隆株和产生 SLT 的菌株的毒素产量做了比较。The chromosomal DNA of S.dysente- riae type Ⅰ W30864 was isolated and diges- ted by EcoRI.The 3—7kb DNA fragments were recovered and ligated with vector pUC- 19.After transformation,the recombinants were screened by SLT gene probe.The posi- tive clones were obtained.The cloned EcoRI fragment containing both ST-A and ST-B subunit gene was about 4.5kb.The cloned ST strain was also detected by Hela-S3 cell for cytotoxicity,and detected by rabbit ileal loop test for enterotoxicity.Besides,the clo- ned strain showed the neurotoxic activity when experimented with mouse.The production of shiga toxin in the cloned strain was 16 times of that of its parent strain S.dysenteriae W30864.The production differences between ST producing stains and SLT producing strain was also tested in our experiment.

关 键 词：痢疾志贺氏菌 毒素 基因克隆 

分 类 号：R394.8[医药卫生—医学遗传学]