ABC毒素的BC成分是一种含有RHS重复的蛋白质封装装置
Jason N Busby1, Santosh Panjikar, Michael J Landsberg
1AgResearch Structural Biology Laboratory, School of Biological Sciences, The University of Auckland, Auckland 1142, New Zealand.
Nature
|August 6, 2013
概括
细菌ABC毒素复合体对于杀虫活性和人类疾病至关重要,需要蛋白质组装才能产生毒性. 这项研究揭示了B-C蛋白质结构,显示了C蛋白质在空洞外中的结合,为毒素传递机制提供了洞察力.
科学领域:
- 结构生物学是结构生物学.
- 细菌蛋白质复合体是一种细菌蛋白质复合体.
- 有毒性的分子机制.
背景情况:
- ABC毒素复合体是具有杀虫剂和潜在人类疾病作用的细菌毒性因子.
- 这些复合体需要A,B和C蛋白质的组合才能达到完全的毒性.
- C蛋白的C端区域具有细胞毒性,但保存不良;其传递机制和B蛋白的作用是未知的.
研究的目的:
- 为了确定B-C蛋白质复合体的高分辨率结构.
- 阐明B蛋白在ABC毒素功能中的作用.
- 了解细胞毒性C蛋白的封装和输送机制.
主要方法:
- 在2.5 Å分辨率的X射线晶体学.
- 分析B-C蛋白质复合体的三维结构.
主要成果:
- B和C蛋白形成了一个大而空洞的结构,封装了C的细胞毒性C终端区域.
- 在B-C复合体上的β-螺旋域调节了与A蛋白的结合.
- 该结构揭示了C与B折叠时的自蛋白解,并确定了C中的重排热点 (RHS) 重复.
结论:
- B-C 结构解释了 C 蛋白质的结合,并提出了其传递的机制.
- 在C蛋白中识别的结构结构和RHS重复很可能保留在相关的细菌和真核蛋白家族中.
- 这项工作为RHS和YD重复蛋白家族的功能提供了第一个结构洞察力,并提出了一种通用蛋白质封装和输送模型.
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