Pathogenicity and drug resistance of enterohemorrhagic

·All the enterohemorrhagic Escherichia coli （EHEC） strains possessed the enteroaggregative Escherichia coli heat-stable enterotoxin 1 （EAST 1）基因同源物，但有两种类型的突变。一种突变类型（1型）与1996年日本的大爆发剧集密切相关。按顺序检测EHEC O 157： H7股与PCR类型1序列，引物集（SHEAST 1a/SHEAST 1b）成功构建。基因同源物也在耶尔森州找到了。鼠疫是一个序列。来自Eleven O 157： H7爆发，只有一次爆发被揭示的感染导致多种抗药物的菌株携带了R型塑料。四环素、链霉菌素和硫醚唑耐药性，以前曾被O 157描述： H7菌株从一个较大的爆发中分离出来，如在美国很好，也在日本与人类和骨骼分离的情况下发现。“药物生物基因的整个序列是确定的。”Adherent EHEC O 157： H7细胞在细胞表面被延长细胞膜覆盖，同时也是异位性E。大肠杆菌（EPEC）被细胞表面上的延长和缠绕的微细菌包裹。EHEC O157 ： H7 （toxin producer）和EPEC （non-toxin producer）。通过延长细胞膜在细胞表面上包裹EHEC的结果可能会在表皮细胞上有效的毒素输送中产生。EHEC菌株属于血清型O 128，用于在一个具有便携式新颖优势因素的链中形成表皮细胞的模式，并产生了EHEC-红细胞素比其他菌株大得多的范围。EHEC-hemolysin诱导了白细胞素-1 β （IL-1 β）的释放，但不是人类单胞菌中的肿瘤坏死因子α（TNF-α），通过PGE 2依赖机制产生了异氮胺抑制的Verotoxin诱导的TNF-α，并减少了Verotoxin在老鼠中的残留。阿尼索达明可能是治疗HUS的潜在药物。

・All the enterohemorrhagic Escherichia coli (EHEC) strains possessed the enteroaggregative Escherichia coli heat-stable enterotoxin 1 (EAST1) gene homologues but with two types of mutations. One of the mutation types (type 1) was strongly associated with the large outbreak episodes in 1996 in Japan. In order to detect EHEC O157 : H7 strains with type 1 sequence by PCR, the primer set (SHEAST1a/SHEAST1b) was successfully constructed. The gene homolugue was also found in the Yersinia. pestis IS sequence.・Out of eleven O157 : H7 outbreaks, only one outbreak revealed infections due to multiple drug-resistant strains which carried an R plasmid. Tetracyclin, streptomycin, and sulfamethoxazole resistance, which was previously described with O157 : H7 strains isolated from a large outbreak as well as sporadic cases in the United States, were also found in Japan with human and bovine isolates. The entire sequences of the drug resiatnce genes were determined.・Adherent EHEC O157 : H7 cells were enwrapped by elongated cell membrane on cell surface, while enteropathogenic E. coli (EPEC) was enwrapped by the elongated and crowded microvilli on cell surface. These phenomena must reflect distinct infectious mechanisms of EHEC O157 : H7 (toxin producer) and EPEC (non-toxin producer). Enwrapping of EHEC on cell surface by elongated cell membrane may result in effective toxin delivery across the epithelial cells.・EHEC strains belonging to serotype O128 adhered to epithelial cells in a pattern of chains with a putative novel adherence factor, and produced EHEC-hemolysin to much greater extents than did the other strains.・EHEC-hemolysin induced the release of interleukin-1β (IL-1β) but not tumor necrosis factor alpha(TNF-α) from human monocyte at subcytocidal concentrations.Anisodamine suppressed Verotoxin-induced TNF-alpha production via PGE2-dependent mechanism, and decreased the lethality of Verotoxin in mice. Anisodamine could be a potential drug for treatment of HUS.