谷氨胺脱和乌比奎丁/NEDD8的功能障碍是由细菌效应器家族诱导的
1Graduate Program in Chinese Academy of Medical Sciences and Beijing Union Medical College, Beijing 100730, China.
概括
细菌蛋白CHBP和Cif通过去amidatingubiquitin和NEDD8.8来抑制无化途径. 这种脱化会损害无素链合成和CRL结合酶活性,影响细胞循环和行动蛋白结构.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 细菌病原体使用效应蛋白来操纵宿主细胞的过程.
- 无处不在的途径对于调节各种细胞功能至关重要.
研究的目的:
- 研究细菌效应蛋白CHBP和Cif.的作用机制.
- 为了确定它们对真核生物无化途径的影响.
主要方法:
- 在实验室中使用乌比奎丁和NEDD8.8进行脱胺酶试验.
- 在Burkholderia和EPEC感染期间进行基于细胞的测定.
- 在Cif效应蛋白的位点定向突变发生.
主要成果:
- CHBP在乌比奎丁和NEDD8中的Gln40脱胺,损害了乌比奎丁链合成.
- 奇夫除氨基酸NEDD8,抑制了库林-RING泛素合酶的活性.
- 在受感染的细胞中,Cif会破坏细胞循环和actin应激纤维.
结论:
- 细菌效应器CHBP和Cif通过脱化准了无处不在化机制.
- 这些效应物调节不良宿主细胞过程,有助于细菌致病的产生.
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