志贺毒素阴性的大肠埃希菌O157菌株的毒力因子检测  

Virulence determinants in non-Shigatoxinogenic Escherichia coli O157 strains isolated from Hangzhou in China

作　　者：潘劲草[1] 孟冬梅[1] 黄志成[1] 祝水芬[1] 姚怀芳[1] 施世锋[1] 

机构地区：[1]杭州市疾病预防控制中心,310006

出　　处：《中华微生物学和免疫学杂志》2001年第2期229-233,共5页Chinese Journal of Microbiology and Immunology

摘　　要：目的　研究志贺毒素阴性的大肠埃希菌O15 7血清群菌株可能携带的毒力因子 ,以确定其致病群类型。方法　对 8株分离自杭州的志贺毒素阴性的大肠埃希菌O15 7血清群菌株及分离自美国和我国江苏的EHECO15 7菌株 ,应用PCR技术检测stx、hly、EPEC和EHEC共有的eaeA、EHEC特异的eaeA ,ELISA检测ETEC的耐热和不耐热肠毒素 ,HEP 2细胞粘附试验测定细菌与上皮细胞的粘附能力 ,并进行菌株质粒图谱分析。结果　 8株志贺毒素阴性的大肠埃希菌O15 7菌株均未检出stx、hly、EHEC特异的eaeA以及ETEC的耐热和不耐热肠毒素 ,仅其中 2株菌株携有EPEC和EHEC共有的eaeA ,另 3株菌株对HEP 2细胞有集聚性粘附能力。结论　目前我国检获的大肠埃希菌O15 7菌株其致病类型表现为多样性 ,部分菌株尚不能明确其毒力因子。EHECO15 7的鉴定必须重视毒力因子的检测。Objective Detecting virulence of non Shigatoxinogenic Escherichia coli O157 strains isolated from Hangzhou in China to determine their pathogroups. Methods Virulence genes and some phenotypes, including stx, hly, EPEC and EHEC general eaeA, EHEC specific eaeA gene with PCR, and ETEC ST and LT with ELISA, and adherence ability to HEP 2 cell, and plasmid pattern, were determined in 8 strains of non Shigatoxinogenic E. coli O157 from Hangzhou, EHEC O157∶H7 strain 933 from US and strain 88 2364 from Jiangsu province in China. Results In 8 strains of non Shigatoxinogenic E. coli O157, there was neither stx, hly, nor EHEC specific eaeA gene, and same for ETEC ST and LT. Only 2 strains were found to be ETEC and EHEC general eaeA gene positive. Other 3 strains showed the abilities of aggregative adherence to HEP 2 cell. Meanwhile, both strains 933 and 88 2364 had stx, hly, or EHEC specific eaeA gene and harbored an 60 megadalton plasmid. Conclusions According to virulence determinants, E. coli O157 strains isolated in China belong to various pathogroups. Some of them have EPEC and EHEC general eaeA gene, but in others no virulence genes were found.

关 键 词：志贺毒素 大肠埃希菌 毒力因子 0157菌株 

分 类 号：R378[医药卫生—病原生物学]