诱导性结束形成的肠病原性大肠杆菌的
J A Girón1, A S Ho, G K Schoolnik
1Department of Microbiology and Immunology, Beckman Center, Howard Hughes Medical Institute, Stanford University, CA 94305.
概括
形成捆绑的 (BFP) 对于肠病原性大肠杆菌 (EPEC) 粘附于小肠并引起儿童腹至关重要. 这些在毒性等离子体上编码的 pili,对于EPEC殖民和感染至关重要.
科学领域:
- 微生物学 微生物学
- 病变的发生和发病.
- 细菌的粘附性 细菌的粘附性
背景情况:
- 肠病原性大肠杆菌 (EPEC) 是儿童腹的一个重要原因.
- EPEC通过在上皮细胞上形成附着的细菌殖民地来殖民小肠.
- 目前正在研究特定细菌结构在EPEC毒性中的作用.
研究的目的:
- 为了研究捆绑形成 pili (BFP) 在 EPEC 附着性和毒性中的作用.
- 描述EPEC中BFP的表达和组成.
- 为了确定BFP表达的遗传基础.
主要方法:
- 在固体介质和HEp-2细胞上培养EPEC.
- 塑固化实验以评估BFP表达.
- 抗血清的生产和对EPEC感染的检测.
- 蛋白质子单元分析和氨基终端序列.
主要成果:
- 当EPEC在血液亚格或HEp-2细胞上生长时,表达出绳状的纤维束,称为BFP.
- 在五个EPEC血清组中观察到BFP表达,所有这些血清组都含有约92基基的毒性等离子体.
- 治愈了等离子体的菌株失去了BFP表达和附着生长.
- 对BFP的抗血清抑制了EPEC感染培养表皮细胞的能力.
- BFP子单位 (19,500达尔顿) 显示氨基末端同质性与Vibrio cholerae毒素对调节的pilin.
结论:
- 结束形成型 (BFP) 是肠病原性大肠杆菌 (EPEC) 的重要毒性因素.
- BFP调解细菌对宿主上皮细胞的粘附,有助于EPEC的病变发生.
- BFP的表达取决于特定的毒性等离子体,突出其遗传基础.
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