Enterohemorrhagic Escherichia coli. Escherichia coli O157:H7 str. Sakai

Escherichia coli O157:H7. This strain is associated with Hamburger disease, which is caused by the contamination of meat products by enterohemorrhagic E. coli (EHEC). The identifier O157:H7 refers to the serotype of EHEC, and reflects the specific antigenic markers found on the surface of the cell. EHEC attaches and effaces to cells in the large intestine. There are numerous differences that distinguish O157:H7 from K-12, hundreds of them associated with genomic islands in either strain, including at least 9 large PAIs in O157:H7 that encode virulence factors. A type III secretion system, the locus of enterocyte effacement, numerous toxins and adhesins, as well as fimbrial gene clusters and iron uptake systems are found in these PAIs. Pathogenicity genes are also found on the plasmid pO157. Escherichia coli O157:H7 strain Sakai. This strain of O157:H7 was isolated in a 1997 outbreak in Sakai, Japan.

大肠埃希菌O157:H7（Escherichia coli O157:H7）。该菌株与汉堡病相关，此病由肠出血性大肠埃希菌（enterohemorrhagic E. coli, EHEC）污染肉制品所引发。标识符O157:H7指代该肠出血性大肠埃希菌的血清型，反映了其细胞表面携带的特异性抗原标记。肠出血性大肠埃希菌可对大肠上皮细胞产生黏附-消除（A/E）病理损伤。大肠埃希菌O157:H7与K-12菌株存在诸多差异，其中数百种差异与二者各自的基因组岛相关，例如O157:H7菌株中至少存在9个编码毒力因子的致病岛（Pathogenicity Islands, PAIs）。这些致病岛携带有Ⅲ型分泌系统、肠细胞黏附脱落位点（locus of enterocyte effacement, LEE）、多种毒素与黏附素，以及菌毛基因簇和铁摄取系统。致病基因同时存在于质粒pO157上。大肠埃希菌O157:H7 Sakai菌株：该O157:H7菌株分离自1997年日本酒井市暴发的食源性疫情中。