多药物传送器的晶体结构显示出一个功能性旋转机制
Satoshi Murakami1, Ryosuke Nakashima, Eiki Yamashita
1Department of Cell Membrane Biology, Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Osaka 567-0047, Japan. mura@sanken.osaka-u.ac.jp
Nature
|August 18, 2006
概括
大肠杆菌中的多种药物排泄输送器AcrB与TolC和AcrA一起工作,具有很大的结合口袋. 晶体结构透露了通过有序的基质结合变化进行药物出口的三步旋转机制.
科学领域:
- 微生物学 微生物学
- 结构生物学 结构生物学
- 生物化学 生物化学
背景情况:
- AcrB 是 Escherichia coli 中的一个关键的多药物流体载体.
- 它与TolC (外膜通道) 和AcrA (膜融合蛋白) 起作用.
研究的目的:
- 通过AcrB阐明多药物运输的结构基础.
- 了解基质结合和出口的机制.
主要方法:
- 使用X射线晶体学来确定AcrB.的结构.
- 对于单独的AcrB和与药物基质复合的结构得到了获得.
主要成果:
- 该AcrB-药物复合体揭示了三种原体在运输周期的不同功能状态.
- 基质位于周等离子域中的一个大,芳香结合口袋内,允许多位点结合.
- 晶体结构捕获了运输周期的不同形态状态.
结论:
- 在毒品出口方面,AcrB采用功能性旋转机制.
- 基质的结合和释放涉及运输体内有序的结构变化.
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